i didnt understand the meaning of for loop
// Given N, find the no set bits (No of 1's in binary represenation)
@Shatabhishek
for( ;n>0;n=n>>1){
ans = ans + (n&1);
}
The loop here is used to iterate through all the bits of a number in its binary representation.
Say n=5, its binary representation will be 101
n>>1 = 010
n>>1(again)= 001
n>>1(again)= 000
This loop will run until n>0
While iterating it will check if the current bit is set or not and accordingly increment the ans variable.
Hope this helps 
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