#include <iostream>
using namespace std;
int main() {
int n, d, sum=0;
cin>>n>>d;
for(int i=1; i<=n; ++i){
if(i%d==0){
sum+=i;
}
}
cout<<"Sum of integers from 1 to N that are divisible by D = "<<sum<<endl;
return 0;
}
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