lab2_1.c

#include <stdio.h>

/*
    Task:
    Write a function `int sum_to_n(int n)` that computes
    the sum of all integers from 1 up to n using a for loop.

    In main():
      - Ask user for a positive integer n
      - If n < 1, print an error
      - Otherwise, call sum_to_n and print the result
*/

int sum_to_n(int n) {
    int sum=0;
    for (int i=1; i<=n; i++) {
        sum +=i;
    }
    return sum; // placeholder
}

int main(void) {
    int n;

    printf("Enter a positive integer n: ");
    scanf("%d", &n);

    if (n<1) {
        printf("error\n");
    } else {
        printf("The sum is: %d\n", sum_to_n(n));
    }

    return 0;
}