#include <stdio.h>

// 0,1,1,2,3,5,8,13,21,34,...
// fibonacci(n)=fibonacci(n-1)+fibonacci(n-2);

int  fibonacci(int);

int fibonacci(int n){
    if (n==1 || n==2){
        return n-1;
    }
    return fibonacci(n-1)+fibonacci(n-2);
}

int main() {
    int n=7;
    printf("the value of fibonacci series at %d is %d",n,fibonacci(n));
    return 0;
}