Write a program that asks the user for a positive integer value. The program should calculate the sum of all the integers from 1 up to the number entered. For example, if the user enters 20, the loop will find the sum of 1, 2, 3, 4, ... 20.
#include <stdio.h>
int main()
{
int i, n, sum = 0;
printf("Enter a positive integer :");
scanf("%d", &n);
for (i = 1; i <= n; i++)
{
sum += i;
}
printf("The sum of first %d numbers is %d.", n, sum);
return 0;
}
Enter a positive integer :20
The sum of first 20 numbers is 210.