// Example program
#include <iostream>
#include <string>
using namespace std;

int getFibN(int n);
int getFibNSum(int n);
int TEST();

int main(){
  // TESTS
  int testResult = TEST(); if (testResult) return testResult;

  int n;
  cout << "n=";
  cin >> n;
  cout << "Summ fib(0) -> fib(n) = " << getFibNSum(n);
}

int getFibNSum(int n){
  int sum = 0;
  do {
    sum += getFibN(n);
  } while (n --> 1);
  return sum;
}

int getFibN(int n){
  int a = 0;
  int b = 1;
  while (n --> 0){
      int t = b;
      b = a+b;
      a = t;
  }
  return a;
}

int TEST(){
  if (getFibN(0) != 0) return 1;
  if (getFibN(1) != 1) return 2;
  if (getFibN(2) != 1) return 3;
  if (getFibN(3) != 2) return 4;
  if (getFibN(4) != 3) return 5;
  if (getFibN(5) != 5) return 6;
  if (getFibN(6) != 8) return 7;
  if (getFibN(7) != 13) return 8;

  if (getFibNSum(0) != 0) return 9;
  if (getFibNSum(1) != 1) return 10;
  if (getFibNSum(2) != 2) return 11;
  if (getFibNSum(3) != 4) return 12;
  if (getFibNSum(4) != 7) return 13;
  if (getFibNSum(5) != 12) return 14;

  return 0;
}