###### tags: `I2P(I)`
# 13647 - Reverse Fibonacci numbers
> [color=#efbe37] If the solution is ambiguous or hard to understand, please contact me. Thanks.
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## Brief
The reverse fibonacci numbers can be reprsent as follow

## Input
There will be three integers G0, G1, and n

## Output
The number Gn

## Solution

#include<stdio.h>

#include <stdio.h>

int G0, G1;

int f(int n) {
    if(n == 0) return G0;
    else if(n == 1) return G1;
    return f(n-2) - f(n-1);
}

int main() {
    int n;

    scanf("%d%d%d", &G0, &G1, &n);

    printf("%d\n", f(n));
}