text: /*
    Write a program to find the sum of first
    n even natural numbers, where n is entered
    by the user.
  */
  
  #include <stdio.h>
  
  int main(void) {
    int sum = 0, n, num = 2;
    printf("Enter how many even natural numbers you want sum up: ");
    scanf("%d", &n);
    for(int i = 0; i < n; i++) {
      sum += num;
      num += 2;
    }
    printf("\nThe sum of given n even natural numbers is %d", sum);
    return 0;
  }