text: /*Exercise 3 - Repetition
  
  Write a C program to calculate the sum of the numbers from 1 to n.
  Where n is a keyboard input.
  
  e.g.
  
  n -> 100
  sum = 1+2+3+....+ 99+100 = 5050
  
  n -> 1-
  sum = 1+2+3+...+10 = 55 */
  
  #include <stdio.h>
  int main() {
    
    int n=0; //declare and initialize variable
    
    printf("Enter number : ");
    scanf("%d",&n);//scan and store number
  
    //repetition for calculte sum
    for(int x=n-1;x>=1;x--){
      n+=x;
    }
    
    //display sum
    printf("Sum = %d",n);
    
    return 0;
  }
  
  