Sum of Fibonacci Numbers at Even Indexes

1#include <stdio.h>
2
3int main() {
4    int n;
5    long long sum = 0;
6    long long fib[100];
7    
8    printf("Enter number of terms: ");
9    scanf("%d", &n);
10    
11    // Generate Fibonacci series
12    fib[0] = 0;
13    fib[1] = 1;
14    for (int i = 2; i < n; i++) {
15        fib[i] = fib[i-1] + fib[i-2];
16    }
17    
18    printf("\nFibonacci series: ");
19    for (int i = 0; i < n; i++) {
20        printf("%lld ", fib[i]);
21    }
22    
23    printf("\n\nFibonacci at even indexes:\n");
24    for (int i = 0; i < n; i += 2) {
25        printf("F(%d) = %lld\n", i, fib[i]);
26        sum += fib[i];
27    }
28    
29    printf("\nSum of Fibonacci at even indexes: %lld\n", sum);
30    
31    return 0;
32}