They have given the constraints, in the subtasks and had not told about the task. So, please tell me where we have to use these constraints, for what?

I have made a simple code for this question that is

and my solution is like this

#include <stdio.h>

int main()

{

long long int n;

scanf("%d", &n);

long long int A[n], i;

for(i=0; i<n; i++)

scanf("%d", &A[i]);

long long int sum=0, j;

for(i=0; i<n; i++)

{

for(j=i+1; j<n; j++)

{

sum+=A[i]&A[j];

}

}

printf("\n %d", sum);

return 0;

}