```c++
#include <iostream>
using namespace std;
int main() {
int n, sum = 0;
cout << "Nhap vao so nguyen duong N: ";
cin >> n;
for (int i = 1; i <= n; i++) {
sum += i;
}
cout << "Tong " << n << " so nguyen lien tiep la: " << sum;
return 0;
}
```
#include <iostream>
int main() {
int N;
std::cout << "Nhap so nguyen duong N: ";
std::cin >> N;
int sum = 0;
for (int i = 1; i <= N; i++) {
sum += i;
}
std::cout << "Tong cua " << N << " so nguyen lien tiep la: " << sum << std::endl;
return 0;
}