include

int sumNumbers(int n) {
int sum = 0;

for (int i = 1; i <= n; i++) {
sum += i;
}
return sum;

}

int main() {
int n;
std::cout << "Enter a number: ";
std::cin >> n;

std::cout << "Sum of numbers from 1 to " << n << " is: " << sumNumbers(n) << std::endl;
return 0;

}