Sum of Fibonacci series in c

#include<stdio.h>

int main(){

    int k,r;

    long int i=0,j=1,f;

    long int sum = 1;

    printf("Enter the number range: ");

    scanf("%d",&r);

    for(k=2;k<r;k++)

   {

         f=i+j;

         i=j;

         j=f;

         sum = sum + j;

    }

    printf("Sum of Fibonacci series is: %ld",sum);

  

    return 0;

}

Sample output:

Enter the number range: 4

Sum of Fibonacci series is: 4