#include <iostream>
using namespace std
int main() {
int N;
cin >> N;
int sum = 0;
for(int i = 1; i<=N; ++i) {
sum += i;
}
cout << endl << "Sum: " << sum;
#include <iostream>
using namespace std
int main() {
int N;
cin >> N;
int sum = 0;
for(int i = 1; i<=N; ++i) {
sum += i;
}
cout << endl << "Sum: " << sum;
}