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Hallowed event.



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So in this video we are going to decide one question reverse a string.



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So for example if the input is Hallowell so hello then space and then word so after reversing the string



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where do the reverse of this thing so D and R O W then space O N and E H.



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So far finding out that it was just start the string from the back.



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So be an odd or w the N or W then space so space then o an edge.



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So O double l e edge.



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So what do you have to do so given input string.



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Give it a posting and you have to convert the input string and doing that he was of the string so that



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is the meaning of the ocean.



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Reverse the string.



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Now let's take one more example.



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So suppose the input string is ABC.



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ABC then what you have to do so you will convert then would sing to which city votes so it reverses



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D C B and A.



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So I hope you understood the question.



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So now let's take one.



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One more example so suppose the input string is a b c b e f so how does this string will be stored inside



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the correct baddy.



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It does very with a then B then C then D then E then F and add then obviously you will have the null



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corrected.



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Now how you can dig the reverse of the string so the procedure is going to be very very simple.



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It is very obvious that you do not have to do anything with the null correct and incorrect is going



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to be present at the last position.



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So that is very obvious.



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Now what does that a lot of the string.



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So this is f then I F E so B C B and A.



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So this is the output and not let us discuss where this what should be our approach.



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So what I will do to obtain that it was the procedure is very simple.



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So the first and the last correct.



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So F will come here even come here.



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Now step the second and the last second will get better.



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So even come here and be welcome here and similarly Gib doing this so C and D will get SAB.



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So Deven go there and C will go mad and you can match so this is FCB CBE f EDI CB.



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So that is the approach that we are going to follow.



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So what is the approach.



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The approach is going to be very very simple.



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I will take two point.



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So this is my start point.



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This is my end point to what I will do.



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I will swap my start point with the end appointed.



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So start point I will move in this direction and point that it will move in this direction.



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So I will loose start plus plus I will do and minus minus.



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And we have to keep doing this.



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How many times so vital the start point does less than and point the you will have to perform these



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steps simple.



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So what do we lose so this start point.



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So E is going to subdivide the F so F will come here and even come here.



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Then you will loose start plus MSO start will come here.



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So this is my new start and this is my new end.



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So be and even get swept so you will lose start.



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Plus plus you will do and minus minus.



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So this is my new start.



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This is my new end so you will swap CND then you will do start plus plus.



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So this will become start and you will do it minus minus.



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So this will become and and now the condition will become void because now the start becomes good then



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end.



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So at this condition you will stop very very simple logic so if you want I can take one more example.



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For example ABC.



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So what I can do this is my start point but this is my and appointed swept starting in.



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So after the sweeping these are going to come here and is going to come here.



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Now start plus plus and minus minus.



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So this is your new start.



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This is your new end and demoed this or in again we will do this mapping.



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So after this wrapping B and C will get swept so C will come here and B will come here and again you



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will update to a start and end.



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So start plus plus and minus minus.



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So this will become your start and this will become your end.



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And at this point you will stop.



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So we have to do the work vital My start is less than and very very simple.



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So let us write the code and then we will write a have a called



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So where do letter turn type so I will not written anything I will just do that in just inside of my



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creek bed and only.



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And let's say the name of the function is reverse what it will take it will take a character that is



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input and what we have to do I have to take two pointers.



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So I have take the first pointer.



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So first point let us take that test name it start.



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So start the loop as it Zito and we loop as it did last year index.



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And in order to find out the last 16 I can use the function and so I would call the function Lent.



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I will give input as I have given poor daddy minus one.



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So this would be good and index.



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So let me check.



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So this is index 0.



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1 2 3 4 and 5.



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So it is very obvious that initially my start will be zero.



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It is very obvious I want to find out.



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And so if you will apply the lend function.



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So what is the lent lent us 1 2 3 4 5 and 6.



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So Lent is actually 6 and the index of 5 and then takes off and is actually 5.



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So that means the index is actually lent minus 1 the index is actually lent to minus 1.



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You can consider the above example also so in this example.



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This was my start.



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So we do not have any confusion I would start start will be initially zero very obvious what is the



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Lent so Lent is actually filled and this is my end so end is actually.



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So this is index 0 and X1 and X2 in our next 3.



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So I can see that my end is actually lent minus 1 I can see my end is actually the Lent minus 1.



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So I'm using the Lent function so we have all read and the code for the Lent function in our previous



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lessons and then what we have to do we have to do swapping and the condition is very simple VI start



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is list and end you will loose wrapping so I have and will function step in C++.



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So I want to sep start and end so Sep start



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and end so I'm swapping and didn't start plus plus and minus minus.



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Very very simple and the return type of the function is wide so we do not have to do anything and here



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what we would what we will do.



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I will call the function so see out



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so Firstly let us call the function to the name of the function is reverse



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then add the function is it was I am passing and put



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and after passing the input let s spent reversed.



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String order can't be reversed.



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Correct Daddy name.



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And we know that the daddy are past biodefense.



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So whatever you are doing changes with the correct in dysfunction function it will get reflected in



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Maine also.



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I'm repeating myself.



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We know that the ads are passed by at a friend's soon so passed by the office.



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So whatever changes you are doing with the ad inside the reverse function it is going to be reflected



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inside.



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Also so no let us based our program



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so.



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Okay.



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So what is happening here at this planet will say the.



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I do not know what is lent because Lent is defined below the reverse function so that this line compiler



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doesn't know what is lent.



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So what we have to do is just copy.



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Sorry just just cut and paste above.



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So we have to write the code of the land above.



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I'm repeating myself this at this link compiler doesn't know what this Lent function because the Lent



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function was written after the release function after this line.



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So that's why it will give you error that it doesn't know what is lent.



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So you have to write lend function before and obviously let us change this one also.



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So it seemed a the guideline name and a hundred.



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So that means I can let me start delimiter by default.



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This new line now let us test our program



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so this is reverse.



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Okay so the name of the ad is actually name the name of the ad is actually name.



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I want to reverse ABC so your string is ABC and the reverse a string is CB.



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Now let us give a b c v e f so your string is a b c d e f and after that it was in it will become F



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E D CBE.



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Now let us test one more time so this time it does give.



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Hello world.



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So hello space world.



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So this is your input string Hello World and this is you reverse the string DL out of the blue space



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0 and then each you can give multiple spaces also saying don't get land can handle multiple spaces also



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for example hello then space space space and then word.



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So this is your input string and after the reversing after the reverse function this is yet output string.



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This is your.



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It was this string so other it was function called is looking perfectly fine and the logic is very simple



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take two pointer one at the beginning one at the end keep slapping them start will move in default word



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not action and pointer will move in the backward direction and you have to keep doing this work while



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you start is actually list and end very very simple.



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So if you have any doubt in discussion you can definitely ask me I will do the next one.



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Bye bye.