Question

write a subroutine that will count the number of 1’s in binary byte

Answer 1

We can use AND operation for this purpose, we can just AND the number with 1 and get the value and keep on adding with the count until the value n becomes 0.

int count(int n){
int count = 0;
while(n>0){
count += (n&1);
n = n >> 1;
}
}

Thus the above subroutine will simply increase the count and make the n to be shift right so as to remove last significant bit.

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