1 00:00:02,070 --> 00:00:03,990 Now the last example I wanna dive 2 00:00:03,990 --> 00:00:08,270 in is this statistics example here. 3 00:00:08,270 --> 00:00:10,600 And here, we will use a while loop. 4 00:00:10,600 --> 00:00:13,260 I can already say that it's probably not 5 00:00:13,260 --> 00:00:15,580 too surprising, given that we haven't 6 00:00:15,580 --> 00:00:18,320 used a while loop in any other example. 7 00:00:18,320 --> 00:00:21,620 And the goal here will be to get that entered number 8 00:00:21,620 --> 00:00:24,470 and upon a click, we wanna roll the dice 9 00:00:24,470 --> 00:00:28,520 in JavaScript and roll it as often as needed 10 00:00:28,520 --> 00:00:32,220 to the derive or to roll that target number, 11 00:00:32,220 --> 00:00:35,350 which therefore must be between one and six. 12 00:00:35,350 --> 00:00:38,340 And we then wanna output all the dice rolls we had 13 00:00:38,340 --> 00:00:41,340 in a list and also output sum summary 14 00:00:41,340 --> 00:00:44,083 as statistics down there in this sentence. 15 00:00:45,200 --> 00:00:47,050 So for that here, I have my 16 00:00:48,130 --> 00:00:52,810 statistics roll the dice example. 17 00:00:52,810 --> 00:00:57,120 And here we all start again by getting access to the button. 18 00:00:57,120 --> 00:01:00,700 The rollDiceButtonElement here. 19 00:01:00,700 --> 00:01:03,370 That sounds like a fitting name and justice 20 00:01:03,370 --> 00:01:07,500 before I'll get access to the button with query selector. 21 00:01:07,500 --> 00:01:11,930 As I did it before by utilizing the section ID, 22 00:01:11,930 --> 00:01:15,250 which in this case is statistics. 23 00:01:15,250 --> 00:01:17,580 So you would stat ID here to get 24 00:01:17,580 --> 00:01:20,383 access to this button like that. 25 00:01:22,410 --> 00:01:27,219 Then, I actually add a little helper function, 26 00:01:27,219 --> 00:01:32,219 rollDice, which will roll the dice for me. 27 00:01:32,450 --> 00:01:34,370 And then the main function that should 28 00:01:34,370 --> 00:01:36,620 be executed when the button is clicked. 29 00:01:36,620 --> 00:01:39,530 We don't need two separate functions, 30 00:01:39,530 --> 00:01:42,050 but I'm doing it here to have a clear separation 31 00:01:42,050 --> 00:01:45,240 between those random number code, which I'll put 32 00:01:45,240 --> 00:01:48,270 into this rollDice function and the main code 33 00:01:48,270 --> 00:01:51,820 for then outputting the roll of list items. 34 00:01:51,820 --> 00:01:55,240 And so on in this main function that is connected 35 00:01:55,240 --> 00:01:57,693 to a click listener on the button. 36 00:01:58,660 --> 00:02:02,387 And I'll name this function, deriveNumberOfDiceRolls. 37 00:02:04,520 --> 00:02:08,360 Like that, and then connect those roll dice 38 00:02:08,360 --> 00:02:11,590 button element with addEventListener 39 00:02:11,590 --> 00:02:16,590 as before upon a click and then here point 40 00:02:17,020 --> 00:02:20,023 at derive number of dice rolls. 41 00:02:21,810 --> 00:02:26,030 Now I'll start here with derive number of dice rolls. 42 00:02:26,030 --> 00:02:29,890 In there, I need to get access to that input 43 00:02:31,100 --> 00:02:34,930 element here and conveniently this has an ID, 44 00:02:34,930 --> 00:02:37,130 which we can use because that will 45 00:02:37,130 --> 00:02:39,450 be the number which we wanna roll. 46 00:02:39,450 --> 00:02:42,167 And therefore we cannot get access to this element and store 47 00:02:42,167 --> 00:02:45,730 it in the constant, which could be named 48 00:02:45,730 --> 00:02:50,730 targetNumberElement or targetNumberInputElement, 49 00:02:54,710 --> 00:02:57,870 by using document get element by ID 50 00:02:57,870 --> 00:03:01,693 and using that ID was added to this input element. 51 00:03:03,915 --> 00:03:07,520 And then we got the entered number, 52 00:03:07,520 --> 00:03:10,660 which is a constant name I already used before. 53 00:03:10,660 --> 00:03:14,030 In an earlier example, I did use this here 54 00:03:14,030 --> 00:03:17,240 and calculate some already, but since I created 55 00:03:17,240 --> 00:03:19,790 it inside of a function, it was exclusive 56 00:03:19,790 --> 00:03:22,260 to this function and I can therefore create another 57 00:03:22,260 --> 00:03:24,440 constant with the same name in a different 58 00:03:24,440 --> 00:03:27,527 function and entered number here, of course is 59 00:03:27,527 --> 00:03:30,633 targetNumberInputElement.value. 60 00:03:31,510 --> 00:03:35,700 Now, I also wanna get access to this unordered list, 61 00:03:35,700 --> 00:03:39,110 which I then use for outputting my dice rolls. 62 00:03:39,110 --> 00:03:41,200 And that has an idea as well. 63 00:03:41,200 --> 00:03:43,930 So here I'll then create a never constant 64 00:03:43,930 --> 00:03:46,240 before I get my entered number, actually 65 00:03:46,240 --> 00:03:48,710 though the order would not matter here. 66 00:03:48,710 --> 00:03:51,730 I just like to group that together since I will have two 67 00:03:51,730 --> 00:03:54,630 constants that select elements and hence someone 68 00:03:54,630 --> 00:03:57,160 to kind of keep them together for readability 69 00:03:57,160 --> 00:04:02,003 purposes and I'll name this the diceRollsListElement here, 70 00:04:03,660 --> 00:04:08,660 where I also use document get element by ID and use that ID. 71 00:04:08,790 --> 00:04:13,200 Then we have the next step and extract the entered number. 72 00:04:13,200 --> 00:04:16,720 And I will also reach out to dice rolls list element, 73 00:04:16,720 --> 00:04:20,310 and set inner HTML to an empty string to, again, 74 00:04:20,310 --> 00:04:25,040 clear any existing list items we might have in there. 75 00:04:25,040 --> 00:04:27,180 We don't have any items initially, 76 00:04:27,180 --> 00:04:29,630 but once we clicked the roll the dice button, 77 00:04:29,630 --> 00:04:32,170 the first time we will have items. 78 00:04:32,170 --> 00:04:34,120 And I always wanna clear those. 79 00:04:34,120 --> 00:04:37,440 If we click that button again, adjust as we cleared 80 00:04:37,440 --> 00:04:39,733 said user data upon a button click. 81 00:04:41,650 --> 00:04:44,120 Now we can continue. 82 00:04:44,120 --> 00:04:45,560 We have that entered number, 83 00:04:45,560 --> 00:04:48,010 which is the number we wanna roll. 84 00:04:48,010 --> 00:04:51,230 So now as a next step here, 85 00:04:51,230 --> 00:04:54,720 I wanna add a while loop where we keep 86 00:04:54,720 --> 00:04:59,533 on rolling numbers until we rolled this entered number. 87 00:05:00,560 --> 00:05:03,390 And a for this I'll add a new variable. 88 00:05:03,390 --> 00:05:06,020 And that is now a variable and not a constant 89 00:05:06,020 --> 00:05:09,630 because it will receive new values 90 00:05:09,630 --> 00:05:11,170 and dead variable could be named, 91 00:05:11,170 --> 00:05:16,170 hasRolledTargetNumber, which is false initially. 92 00:05:17,120 --> 00:05:19,880 It's a Boolean value, which I store in here. 93 00:05:19,880 --> 00:05:23,140 Hence I have dis variable naming here, 94 00:05:23,140 --> 00:05:25,460 which answers a question basically, 95 00:05:25,460 --> 00:05:30,460 which is how you typically do name your Boolean variables. 96 00:05:30,550 --> 00:05:33,300 And that's false initially because we haven't rolled our 97 00:05:33,300 --> 00:05:36,910 target number yet, but we wanna set it to true inside 98 00:05:36,910 --> 00:05:39,403 of the dwell loop once we did roll it. 99 00:05:40,370 --> 00:05:44,380 So here I will keep on rolling as long as we have not. 100 00:05:44,380 --> 00:05:47,980 Hence the exclamation mark rolled the target number 101 00:05:49,130 --> 00:05:50,980 and then here between curly braces, 102 00:05:50,980 --> 00:05:53,400 we have the actual code for this loop 103 00:05:53,400 --> 00:05:56,460 and that's where we now wanna roll a number. 104 00:05:56,460 --> 00:05:59,880 So here I will execute this rollDice function, 105 00:05:59,880 --> 00:06:01,910 even though it's not doing anything yet, 106 00:06:01,910 --> 00:06:06,463 we'll add the logic soon, I'll execute rollDice. 107 00:06:06,463 --> 00:06:09,550 And I simply expect that this function will 108 00:06:09,550 --> 00:06:13,260 return a random number between one and six. 109 00:06:13,260 --> 00:06:17,770 So here I then have my rolled number and that's a constant 110 00:06:17,770 --> 00:06:22,350 because it will be recreated for every while loop execution. 111 00:06:22,350 --> 00:06:25,620 So it's not reassigned, but it's a brand new variable, 112 00:06:25,620 --> 00:06:28,190 a brand new constant that will be created 113 00:06:28,190 --> 00:06:31,020 for every while loop iteration. 114 00:06:31,020 --> 00:06:34,583 And it will hold that rolled number between one and six. 115 00:06:35,760 --> 00:06:40,760 And now we can check if rolled number is equal to entered 116 00:06:42,470 --> 00:06:46,280 number, and I'm using two equal signs instead 117 00:06:46,280 --> 00:06:50,350 of free equal signs here because entered number 118 00:06:50,350 --> 00:06:53,490 when retrieved from the value property 119 00:06:53,490 --> 00:06:57,160 of an input element will always be a string. 120 00:06:57,160 --> 00:07:00,130 It might be a number that was entered by the user, 121 00:07:00,130 --> 00:07:02,380 but it will be a pipe string. 122 00:07:02,380 --> 00:07:05,960 That's just how HTML and JavaScript works. 123 00:07:05,960 --> 00:07:08,750 When you get the value of an input field, 124 00:07:08,750 --> 00:07:13,160 it's always a string, even if the input is of pipe number. 125 00:07:13,160 --> 00:07:15,660 And even if the user did enter a number, 126 00:07:15,660 --> 00:07:17,780 JavaScript does not care about that. 127 00:07:17,780 --> 00:07:21,840 You always get a string and therefore this entered number, 128 00:07:21,840 --> 00:07:26,010 even though it is a number of value will be a pipe string. 129 00:07:26,010 --> 00:07:30,010 And hence we could either convert it to a number this could 130 00:07:30,010 --> 00:07:34,090 easily be done by adding a plus here in front of it. 131 00:07:34,090 --> 00:07:36,450 That's a quick way of converting a string 132 00:07:36,450 --> 00:07:40,450 to a number in JavaScript, or we don't do this. 133 00:07:40,450 --> 00:07:43,610 And instead we just use the double equal sign comparison 134 00:07:43,610 --> 00:07:48,130 operator here to compare a number value, 135 00:07:48,130 --> 00:07:50,730 which roll dice we'll return eventually 136 00:07:50,730 --> 00:07:55,723 to a string value and check for value equality only. 137 00:07:56,770 --> 00:07:58,930 And inside of this if statement, 138 00:07:58,930 --> 00:08:02,620 we can then set hasRolledTargetNumber 139 00:08:02,620 --> 00:08:06,543 to true if that here yields true. 140 00:08:08,010 --> 00:08:09,840 Now this is one way of doing it, 141 00:08:09,840 --> 00:08:12,740 but it's actually a bit too long on the otherhand 142 00:08:12,740 --> 00:08:16,390 it is hopefully pretty easy to understand. 143 00:08:16,390 --> 00:08:20,480 Nonetheless, I'll comment it out because if you write 144 00:08:20,480 --> 00:08:24,300 a if statement to then store a Boolean value, 145 00:08:24,300 --> 00:08:26,630 based on the result of this, if condition 146 00:08:26,630 --> 00:08:30,220 in another variable, then you can shorten this 147 00:08:30,220 --> 00:08:33,309 and you can just write hasRolledTargetNumber 148 00:08:33,309 --> 00:08:36,883 equal to the result of this comparison. 149 00:08:38,140 --> 00:08:42,130 Because keep in mind these comparison operators yield a 150 00:08:42,130 --> 00:08:45,670 Boolean value, true or false. 151 00:08:45,670 --> 00:08:48,260 And if that's what we wanna store in a variable, 152 00:08:48,260 --> 00:08:50,200 we don't need the extra if check. 153 00:08:50,200 --> 00:08:52,700 We can just store the result of this Boolean 154 00:08:52,700 --> 00:08:56,530 comparison in this variable here. 155 00:08:56,530 --> 00:08:58,700 It's not something we did up to this point 156 00:08:58,700 --> 00:09:00,720 in the course, but it is something which 157 00:09:00,720 --> 00:09:03,710 is also quite common to do in JavaScript. 158 00:09:03,710 --> 00:09:07,150 If you have a variable or any place in your code 159 00:09:07,150 --> 00:09:09,330 that needs a Boolean value, that should 160 00:09:09,330 --> 00:09:11,750 be the result of some comparison. 161 00:09:11,750 --> 00:09:13,360 You don't need the if check. 162 00:09:13,360 --> 00:09:15,260 You can just store the comparison 163 00:09:15,260 --> 00:09:18,450 result itself in the variable. 164 00:09:18,450 --> 00:09:20,460 So this will yield true or false. 165 00:09:20,460 --> 00:09:22,970 And hence we store true or false 166 00:09:22,970 --> 00:09:26,093 in that has rolled target number variable. 167 00:09:27,300 --> 00:09:31,757 And if this should be true, this will no longer yield 168 00:09:31,757 --> 00:09:34,010 true, because we have the negation operator 169 00:09:34,010 --> 00:09:36,110 and we would leave the while loop 170 00:09:36,110 --> 00:09:39,700 once we rolled our target number therefore. 171 00:09:39,700 --> 00:09:42,400 And hence now after does while loop, 172 00:09:42,400 --> 00:09:46,470 we can output some summary statistics. 173 00:09:46,470 --> 00:09:51,470 We can say how many rolls it took us to roll the target 174 00:09:52,230 --> 00:09:57,230 number for this we'll need access to these spans here, 175 00:09:57,420 --> 00:10:00,540 where we do output our summary data. 176 00:10:00,540 --> 00:10:02,780 And we also need to keep track 177 00:10:02,780 --> 00:10:04,663 of the number of rolls we have. 178 00:10:05,780 --> 00:10:08,950 Now I'll first of all, get access to these spans here. 179 00:10:08,950 --> 00:10:12,740 And the first span has an idea of output, total rolls, 180 00:10:12,740 --> 00:10:15,140 so I'll create a constant here, 181 00:10:15,140 --> 00:10:20,140 output total rolls element where I use 182 00:10:20,200 --> 00:10:23,813 document get element by ID and use that ID. 183 00:10:25,030 --> 00:10:27,330 And then we have the second span 184 00:10:27,330 --> 00:10:30,410 where we output that target number. 185 00:10:30,410 --> 00:10:34,410 And this span has an ID of output target number. 186 00:10:34,410 --> 00:10:36,673 So here we can now use this and store 187 00:10:36,673 --> 00:10:39,350 this in a constant as well. 188 00:10:39,350 --> 00:10:43,970 The output target number element that could 189 00:10:43,970 --> 00:10:46,940 be a name we use and then use document 190 00:10:46,940 --> 00:10:51,063 get element by ID output, target number. 191 00:10:52,640 --> 00:10:54,900 Now for output target number element, 192 00:10:54,900 --> 00:10:57,920 we can already set the text content. 193 00:10:57,920 --> 00:11:02,860 So here we can set text content equal to the enteredNumber. 194 00:11:02,860 --> 00:11:05,830 So the entered number, which we extract up here, 195 00:11:05,830 --> 00:11:07,370 because we just wanna repeat 196 00:11:07,370 --> 00:11:08,800 that entered number down there. 197 00:11:08,800 --> 00:11:12,700 So that's easy, now for the number of rolls, 198 00:11:12,700 --> 00:11:16,030 we will have to keep track of those rolls. 199 00:11:16,030 --> 00:11:19,870 And for that, I'll create another helper variable here, 200 00:11:19,870 --> 00:11:24,870 which will name numberOfRolls, and which is 0 initially. 201 00:11:25,930 --> 00:11:29,403 And it is created before we entered that while loop, 202 00:11:30,270 --> 00:11:34,850 because inside of that, while loop, I wanna change it. 203 00:11:34,850 --> 00:11:39,430 There I want to set numberOfRolls equal 204 00:11:39,430 --> 00:11:44,430 to numberOfRolls + 1, I wanna increment it by 1. 205 00:11:45,810 --> 00:11:47,460 And of course, if that's the goal we can 206 00:11:47,460 --> 00:11:49,670 always adjust used is short-hand. 207 00:11:49,670 --> 00:11:53,280 We learned about with the plus plus operator, 208 00:11:53,280 --> 00:11:54,690 which is the same. 209 00:11:54,690 --> 00:11:57,490 This will increment number of rolls by one 210 00:11:57,490 --> 00:12:00,170 and store that new value in that variable 211 00:12:01,070 --> 00:12:02,760 and therefore a number of rolls in the end, 212 00:12:02,760 --> 00:12:05,080 will it be the number of rolls that took us. 213 00:12:05,080 --> 00:12:10,080 And hence we can set output total rolls element text, 214 00:12:10,260 --> 00:12:15,260 content, equal to number of rolls like this. 215 00:12:15,810 --> 00:12:18,680 With that, we're outputting this, but we still don't 216 00:12:18,680 --> 00:12:21,100 create a list item for every roll. 217 00:12:21,100 --> 00:12:24,220 And of course we're not rolling the dice at all. 218 00:12:24,220 --> 00:12:26,000 We'll do that as a last step. 219 00:12:26,000 --> 00:12:29,370 First of all, let's create a list item for every roll 220 00:12:29,370 --> 00:12:33,840 where we log that roll to the screen, basically. 221 00:12:33,840 --> 00:12:38,500 And for that maybe here off after number of rolls, 222 00:12:38,500 --> 00:12:43,500 I wanna create a new roll list element 223 00:12:44,290 --> 00:12:47,840 with document create element, and we create a list 224 00:12:47,840 --> 00:12:52,470 item here as we did it a couple of minutes before as well. 225 00:12:52,470 --> 00:12:57,470 And then on this new roll list element or list item element, 226 00:12:57,680 --> 00:13:00,730 if you wanna be super precise here with our naming 227 00:13:00,730 --> 00:13:03,410 on that element, which be created, 228 00:13:03,410 --> 00:13:07,650 I wanna set the text content here to again, 229 00:13:07,650 --> 00:13:09,870 a little bit of a more complex string. 230 00:13:09,870 --> 00:13:12,150 So again, I will create a helper constant 231 00:13:12,150 --> 00:13:17,150 for that the output text constant, which says roll. 232 00:13:18,120 --> 00:13:21,230 And then I wanna have to number of that roll, 233 00:13:21,230 --> 00:13:24,550 which is number of rolls here. 234 00:13:24,550 --> 00:13:26,940 Since I'm doing that after incrementing number 235 00:13:26,940 --> 00:13:30,440 of rolls that will already be the correct number. 236 00:13:30,440 --> 00:13:33,630 And then I wanna have a semi colon and a white space. 237 00:13:33,630 --> 00:13:36,340 Hence I concatenate that string 238 00:13:36,340 --> 00:13:39,463 and then output the rolled number. 239 00:13:40,860 --> 00:13:44,740 And now we can set this output text here as a value 240 00:13:44,740 --> 00:13:49,250 for the text content on the new roll list item element. 241 00:13:49,250 --> 00:13:52,860 And we can then use this list here, 242 00:13:52,860 --> 00:13:57,460 the dice rolls list element to append this item. 243 00:13:57,460 --> 00:13:59,790 So on that dice rolls list element, 244 00:13:59,790 --> 00:14:03,530 I call append and append the new roll list, 245 00:14:03,530 --> 00:14:05,303 item element like this. 246 00:14:06,160 --> 00:14:10,450 With that, we should be outputting that roll result. 247 00:14:10,450 --> 00:14:12,060 Now we just need to make sure 248 00:14:12,060 --> 00:14:15,030 that we do actually roll a random number. 249 00:14:15,030 --> 00:14:18,200 So we need to work on that rollDice function. 250 00:14:18,200 --> 00:14:21,320 And here in this function, we will utilize some 251 00:14:21,320 --> 00:14:24,010 built in functionality, JavaScript offers 252 00:14:24,010 --> 00:14:26,440 to us when it comes to working with random 253 00:14:26,440 --> 00:14:29,740 numbers and with numbers in general. 254 00:14:29,740 --> 00:14:32,190 We wanna return the value of course, 255 00:14:32,190 --> 00:14:34,300 and that value, which I wanna return 256 00:14:34,300 --> 00:14:35,217 here is basically a random number. 257 00:14:35,217 --> 00:14:40,217 For this we have Math.random just as we 258 00:14:41,450 --> 00:14:44,460 have console.log for logging something. 259 00:14:44,460 --> 00:14:48,000 We have a globally available math object, 260 00:14:48,000 --> 00:14:49,500 which is built into the browser. 261 00:14:49,500 --> 00:14:52,760 So to say, which has random method, 262 00:14:52,760 --> 00:14:54,420 which returns a random number 263 00:14:54,420 --> 00:14:58,960 between zero and one, zero is included. 264 00:14:58,960 --> 00:15:01,720 One is excluded and it returns 265 00:15:01,720 --> 00:15:04,930 any floating point number in between basically. 266 00:15:04,930 --> 00:15:07,793 So it returns value is like this. 267 00:15:10,070 --> 00:15:11,820 Now here, we don't want a number 268 00:15:11,820 --> 00:15:15,323 between zero and one though, but between one and six. 269 00:15:16,180 --> 00:15:21,180 Therefore we'll start by multiplying Math.random with six. 270 00:15:21,500 --> 00:15:24,863 Now we have a random number between zero and six. 271 00:15:26,310 --> 00:15:31,310 Now we don't want all these floating point numbers though. 272 00:15:31,620 --> 00:15:33,810 We want integers only. 273 00:15:33,810 --> 00:15:35,870 And for that, we have another built in 274 00:15:35,870 --> 00:15:40,870 method on this math object and that's the floor method, 275 00:15:40,890 --> 00:15:45,600 which we can wrap around this result, which we derived here. 276 00:15:45,600 --> 00:15:49,670 So we pass the result of calling Math.random 277 00:15:49,670 --> 00:15:53,800 and multiplying it with six as a parameter value 278 00:15:53,800 --> 00:15:58,410 to Math.floor and Math.floor will 279 00:15:58,410 --> 00:16:01,060 simply round dead value down. 280 00:16:01,060 --> 00:16:04,150 It will round it down to the nearest integer. 281 00:16:04,150 --> 00:16:07,370 It cuts any decimal numbers basically. 282 00:16:07,370 --> 00:16:12,370 So if we have 5.64 that would be rounded down to just five. 283 00:16:13,440 --> 00:16:15,940 That's what Math.floor does. 284 00:16:15,940 --> 00:16:20,670 So let me just make this clear here what Math.floor does. 285 00:16:20,670 --> 00:16:22,610 That's what it does. 286 00:16:22,610 --> 00:16:24,050 Now, that's still not all though, 287 00:16:24,050 --> 00:16:25,660 because that will give us a number 288 00:16:25,660 --> 00:16:30,083 between zero and six, six excluded. 289 00:16:30,920 --> 00:16:33,040 And therefore what we need to do as a last step 290 00:16:33,040 --> 00:16:36,180 is we need to add one because now we have 291 00:16:36,180 --> 00:16:38,290 a random number between one and six. 292 00:16:38,290 --> 00:16:41,120 Since we simply add one to our random number 293 00:16:41,120 --> 00:16:43,950 between zero and five, which we got effectively 294 00:16:43,950 --> 00:16:46,320 with just discoed and this code. 295 00:16:46,320 --> 00:16:48,660 And therefor now, we have a function that yields 296 00:16:48,660 --> 00:16:51,613 a random number between one and six. 297 00:16:53,220 --> 00:16:55,450 And now that should be all, was quite 298 00:16:55,450 --> 00:16:57,690 a lot of work, but it should be all. 299 00:16:57,690 --> 00:17:01,970 If we now is save that and I enter four, 300 00:17:01,970 --> 00:17:05,619 then if I click this button, I see some output 301 00:17:05,619 --> 00:17:07,890 and that output output will differ every 302 00:17:07,890 --> 00:17:09,869 time I click this button and you'll see 303 00:17:09,869 --> 00:17:13,792 how many rolls it's took to roll a four. 304 00:17:15,710 --> 00:17:20,060 So that's now this example implemented as well. 305 00:17:20,060 --> 00:17:25,060 And what we see here is a great use case for a while loop, 306 00:17:25,680 --> 00:17:29,900 where we keep on executing some code until a certain 307 00:17:29,900 --> 00:17:32,623 condition is not met anymore.