What's the problem with this code? I want to take two strings in input, reverse the first and then compare it with the second.

Question

https://code.sololearn.com/cQV7aqZZl92w/?ref=app

Answer 1

Check Line 11 of your code.
You are going from end to start of the string and at the same time you are incrementing the counter. You need to decrement the value of i if you are traversing string from end to start.
Just change that line to this :
for(int i=leng-1; i>=0; i--)

Answer 2

You could also use a for each loop:
for(char c : a.toCharArray()){
res = c + res}
for additional speed you could also append the chars to a StringBuilder instead of resizing the String every time, but this isn't necessary