int pop_count (unsigned);
int pop_count (unsigned bitstring){
int i;
int population_count = 0;
for(i=0;i<32;i++){
if (bitstring & 0x1){
population_count ++;
}
bitstring = bitstring >> 1;
}
return population_count;
}
int main () {
unsigned input = 0xf3f3;
unsigned result = 0;
result = pop_count(input);
printf("\n population count is %d", result);
return 1;
}