#include <iostream>
using namespace std;
 
int main() {
    int number;
    int sum = 0;
 
    // Ask for input
    cout << "Enter a positive integer: ";
    cin >> number;
 
    // Input validation
    while (number < 0) {
        cout << "Invalid input! Please enter a positive integer: 50 ";
        cin >> number;
    }
 
    // Loop to calculate sum
    for (int i = 1; i <= number; i++) {
        sum += i;
    }
 
    // Display result
    cout << "The sum of numbers from 1 to 50 " << number << " is: " << sum << endl;
 
    return 0;
}
 

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