1 00:00:02,430 --> 00:00:03,300 Hi, guys. 2 00:00:03,390 --> 00:00:04,020 What's up? 3 00:00:04,560 --> 00:00:08,220 So today we are going to solve one more interesting problem on functions. 4 00:00:08,820 --> 00:00:12,960 So the Brownless statement is a function Laura done. 5 00:00:15,750 --> 00:00:16,980 Factorial of a number. 6 00:00:18,660 --> 00:00:20,210 Thought he'd done factorial over. 7 00:00:20,700 --> 00:00:21,120 No. 8 00:00:23,820 --> 00:00:24,770 So what is Vectorial? 9 00:00:25,350 --> 00:00:27,060 So five factorial. 10 00:00:27,140 --> 00:00:31,050 It was five to four and two, three in total. 11 00:00:31,170 --> 00:00:32,820 And doing what you can, right? 12 00:00:33,360 --> 00:00:35,760 One and two and two, three and two forward. 13 00:00:35,780 --> 00:00:36,170 And two. 14 00:00:36,320 --> 00:00:37,830 Five, which is 120. 15 00:00:38,790 --> 00:00:40,320 So what is one factorial? 16 00:00:40,930 --> 00:00:42,270 And there's one more. 17 00:00:42,280 --> 00:00:43,320 There's two factorial. 18 00:00:43,500 --> 00:00:44,670 It is one and two. 19 00:00:44,820 --> 00:00:46,690 Two or three factorial. 20 00:00:47,280 --> 00:00:49,890 One and two doing two, three, six. 21 00:00:50,310 --> 00:00:51,570 What is four factorial? 22 00:00:51,690 --> 00:00:52,230 One and two. 23 00:00:52,230 --> 00:00:52,800 Doing two. 24 00:00:53,010 --> 00:00:53,600 Three and two. 25 00:00:53,910 --> 00:00:54,250 Four. 26 00:00:54,390 --> 00:00:56,190 Which is twenty four. 27 00:00:57,030 --> 00:00:57,300 OK. 28 00:00:57,720 --> 00:01:05,130 So given a number and given a number, then we have to write a function that will on the factorial of 29 00:01:05,130 --> 00:01:05,960 that number. 30 00:01:08,530 --> 00:01:12,070 So how we can find factory number, for example, numbers. 31 00:01:12,220 --> 00:01:13,720 And so what do we do? 32 00:01:14,010 --> 00:01:16,540 One and two, two and three into four. 33 00:01:17,860 --> 00:01:18,160 And. 34 00:01:19,800 --> 00:01:22,420 OK, so I just we have to multiply all this numbers. 35 00:01:22,870 --> 00:01:23,770 So I need a loop. 36 00:01:24,130 --> 00:01:28,440 Initially, the loop will start from one Lowville go, then end. 37 00:01:29,080 --> 00:01:32,710 And what I will do, I will take a variable answer. 38 00:01:32,830 --> 00:01:34,320 Answer will initially be one. 39 00:01:34,720 --> 00:01:36,090 So answer quiz. 40 00:01:36,370 --> 00:01:36,820 Answer. 41 00:01:37,340 --> 00:01:38,620 Multiply by I. 42 00:01:39,970 --> 00:01:40,230 OK. 43 00:01:41,200 --> 00:01:41,860 So let's see. 44 00:01:49,910 --> 00:01:53,600 Function Factorial Nard CBB. 45 00:02:04,380 --> 00:02:10,500 So what I have to do, first of all, I will take a number and as input from the user who's Vectorial 46 00:02:10,500 --> 00:02:12,390 and we have to conclude. 47 00:02:13,810 --> 00:02:15,880 So we need a factorial function. 48 00:02:16,510 --> 00:02:19,710 Let's say the name of defect, all function is fact. 49 00:02:20,890 --> 00:02:25,690 It will take and as input was the toll, it has to return. 50 00:02:26,200 --> 00:02:29,410 So since it will be done something, I will have to store it. 51 00:02:29,770 --> 00:02:32,100 So let's say in Tancer, it was fact. 52 00:02:32,620 --> 00:02:36,430 Now, after getting the answer, I will print my answer. 53 00:02:36,910 --> 00:02:38,650 So that is all that we have to do. 54 00:02:39,040 --> 00:02:41,160 Now let us write the function fact. 55 00:02:41,740 --> 00:02:43,780 So this function will return an integer. 56 00:02:44,080 --> 00:02:47,950 That is the fact all of the number and the name of the function is fact. 57 00:02:48,310 --> 00:02:51,780 It will take a number as input was factory. 58 00:02:52,090 --> 00:02:53,140 It will calculate. 59 00:02:54,520 --> 00:02:54,910 So. 60 00:02:57,330 --> 00:03:01,230 Let's say I am having a variable and dasa, which is initialized to one. 61 00:03:02,520 --> 00:03:02,750 OK. 62 00:03:02,910 --> 00:03:06,660 And now we have to multiply starting from one. 63 00:03:07,050 --> 00:03:19,580 So I equals when I last then ordered close to an A plus plus answer equals answer my two blabby I. 64 00:03:21,300 --> 00:03:25,910 And after calculating the answer we have to read Dundy answer. 65 00:03:28,270 --> 00:03:29,860 OK, so this is all that we have to do. 66 00:03:30,670 --> 00:03:32,460 So now let us test our program. 67 00:03:35,880 --> 00:03:43,170 Led to the relief and is for so 24 is difficult enough for now, let's see, where does the factor of 68 00:03:43,170 --> 00:03:43,620 five? 69 00:03:43,710 --> 00:03:46,560 So the factor of five is one 20. 70 00:03:47,130 --> 00:03:48,810 So our program is working fine. 71 00:03:49,290 --> 00:03:55,050 And why I initially started with when I feel a lot initialise the answer will contain a garbage value. 72 00:03:55,260 --> 00:03:59,430 So we have to initialize, just like we used to initialize some equals zero. 73 00:04:00,030 --> 00:04:01,170 So we have to initialize it. 74 00:04:02,370 --> 00:04:07,170 So you can also start from two, because multiplication with one doesn't have an impact. 75 00:04:09,580 --> 00:04:11,020 So five victory leaves 120. 76 00:04:12,100 --> 00:04:19,030 One more thing that I want to tell you is so you people should not get confused, this variable answer 77 00:04:19,120 --> 00:04:20,500 and this variable answer. 78 00:04:20,590 --> 00:04:21,550 They both are different. 79 00:04:21,640 --> 00:04:21,880 Why? 80 00:04:21,880 --> 00:04:24,310 They are different because their scope are different. 81 00:04:24,670 --> 00:04:28,600 The scope of this variable answer is between this and this. 82 00:04:29,050 --> 00:04:32,050 And the scope of this answer is this. 83 00:04:32,530 --> 00:04:33,490 And this. 84 00:04:34,640 --> 00:04:38,030 OK, so here answer is a local variable. 85 00:04:38,750 --> 00:04:43,580 This is also a local variable and these scopes are different. 86 00:04:43,940 --> 00:04:46,820 OK, so these variables are different. 87 00:04:47,150 --> 00:04:48,290 Don't get confused. 88 00:04:48,590 --> 00:04:50,060 They don't have any relation. 89 00:04:50,420 --> 00:04:55,100 Also, this variable in and this variable and they're also different. 90 00:04:55,460 --> 00:05:01,610 The scope of this variable is between this bracket and this bracket, the scope of this variable and 91 00:05:01,750 --> 00:05:04,510 as between this record and this beckert. 92 00:05:04,910 --> 00:05:08,540 So I said and n they both are different. 93 00:05:08,890 --> 00:05:09,190 OK. 94 00:05:10,280 --> 00:05:11,720 They both are different. 95 00:05:12,390 --> 00:05:12,670 Why? 96 00:05:12,800 --> 00:05:14,690 Because their scores are different. 97 00:05:14,900 --> 00:05:16,460 So do not get confused at all. 98 00:05:17,120 --> 00:05:18,770 So let me show you what I want to say. 99 00:05:20,420 --> 00:05:24,770 So for example, I am changing the value of and let's say it was two. 100 00:05:26,100 --> 00:05:26,400 OK. 101 00:05:26,870 --> 00:05:34,340 And for example, I'm here I am bringing the value of an S.O.S. out. 102 00:05:35,720 --> 00:05:36,950 I'm bringing the videophone. 103 00:05:37,700 --> 00:05:39,080 And let's come into doubt. 104 00:05:41,450 --> 00:05:44,270 OK, so let's give fifers input. 105 00:05:45,260 --> 00:05:48,110 So I'm giving fifers input and I am printing the value of. 106 00:05:48,680 --> 00:05:48,830 So. 107 00:05:48,920 --> 00:05:50,570 Value and will not change. 108 00:05:51,050 --> 00:05:52,440 So five is getting printed. 109 00:05:52,790 --> 00:05:53,050 OK. 110 00:05:54,290 --> 00:05:55,280 So what I did is. 111 00:05:56,610 --> 00:05:59,300 So what I did I give five input. 112 00:05:59,660 --> 00:06:03,960 I call this function and this function change the value of N two two. 113 00:06:04,280 --> 00:06:08,250 But when I am printing the answer is still five. 114 00:06:08,270 --> 00:06:09,770 The value of end is still five. 115 00:06:10,060 --> 00:06:10,350 Why. 116 00:06:10,580 --> 00:06:13,890 Because this n and this n they are different. 117 00:06:14,290 --> 00:06:14,580 OK. 118 00:06:15,080 --> 00:06:17,960 They don't have any relationship and they're completely different. 119 00:06:19,310 --> 00:06:19,540 OK. 120 00:06:20,600 --> 00:06:21,890 So how are trends. 121 00:06:22,730 --> 00:06:23,780 This is my call stack. 122 00:06:23,810 --> 00:06:25,040 And this is my function. 123 00:06:25,040 --> 00:06:26,800 Main function mean. 124 00:06:26,900 --> 00:06:27,830 This is calling. 125 00:06:28,100 --> 00:06:32,600 It will call function in fact when in fact function will complete. 126 00:06:33,120 --> 00:06:34,510 When in fact function well you're done. 127 00:06:34,520 --> 00:06:35,540 It will be popped out. 128 00:06:36,680 --> 00:06:44,480 I will start executing my mean from line number 24 because this is coming command and then. 129 00:06:46,170 --> 00:06:49,950 When the work of mine gets completed, I will pop it out. 130 00:06:50,700 --> 00:06:55,880 And finally my Kostic will become empty and my programmers finish. 131 00:06:56,100 --> 00:06:56,340 Oh. 132 00:07:00,480 --> 00:07:04,850 OK, so remember this answer variable. 133 00:07:05,310 --> 00:07:12,540 This answer variable, completely different, this and this, and they are completely different. 134 00:07:13,200 --> 00:07:13,500 OK. 135 00:07:16,350 --> 00:07:19,650 So instead of storing you can directly, you can also print dramatically. 136 00:07:23,110 --> 00:07:30,040 You can also see out fact often and let's be clear, did. 137 00:07:36,810 --> 00:07:38,610 OK, so how does working. 138 00:07:40,810 --> 00:07:41,260 OK, guys. 139 00:07:41,350 --> 00:07:42,640 So this is it for this video. 140 00:07:43,900 --> 00:07:46,120 If you have any doubt, feel free to ask. 141 00:07:46,180 --> 00:07:46,690 Thank you.