Bitwise operator problem (going into tle)

#1

sol: https://ide.codingblocks.com/s/381774
prob: https://hack.codingblocks.com/app/contests/1975/65/problem

#2

Hey @raghav007 the logic you are using is wrong
Use this instead

int countSetBits(int a, int b){
	int ans=0;
	for(int i=a;i<=b;i++){
        int j=0;
		while( i>>j ){ 
			ans +=((i>>j)&1); 
			j++;
		}
	}
	return ans;
}
#3

im not able to understand this implementation after the first for loop like why is j = 0 and why are we shifting i j times

#4

Extracting all the set bits from i at every ity digit means if i is

i = 10110
So j is traversing from back
1.       10110
             ^
            J
2.       10110
           ^
           J
.
.
.


5.       10110
          ^
         J
#5

oh okay but how can j act as a pointer because 10110 is not in an array

#6

It’s not a pointer , j pointing to any index means that
If it’s pointing
10111
—^
—j000
Which means that j is one and remaining digit behind is zero

#7

Then we do and of j and that index and count if it’s a set bit or not

#8

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