This is the link for the problem. below is my solution
enter code here
#include<iostream>
using namespace std;
#define loop(i,j,k) for( int i = j; i < k; i++)
int main()
{
int T;
cin >> T;
loop(i,0,T)
{
long long unsigned int a, d, n, x, count, m;
count = 0;
m = 215372682525ll;
cin >> a >> d >> n >> x;
long long int s = 1;
for (int j = n; j >= 0; j--)
{
count = (count + (((a + (j * d)%m))% m) * (s % m)) % m;
s = (s * x) % m;
}
cout << count <<endl;
}
//getchar();getchar();getchar();
return 0;
}
I request you to point out any mistake that i have done⦠I will be very grateful to you