#include <stdio.h>
int fibonacci (int n){ int i, a = 0, b = 1, c;

    if(n == 0)
        return 0;
    if(n == 1)
        return 1;

    for(i = 2; i <= n; i++){
        c = a + b;
        a = b;
        b = c;
    }

    return b;

}
int main(){
printf("%d", fibonacci(5));
return 0;
}