数当てさせゲーム

guess_my_number.cpp

#include <iostream>

int small = 1;
int big = 100;

int guessMyNumber()
{
  return (small + big) / 2;
}

void smaller()
{
  big = (guessMyNumber() - 1);
}

void bigger()
{
  small = (guessMyNumber() + 1);
}

int main(int argc, char const* argv[])
{
  int result = 0;

  while (true) {
    std::cout << guessMyNumber() << std::endl;
    std::cout << "smaller:0, just:1, bigger: 2 > ";
    std::cin >> result;
    switch (result) {
      case 0:
        smaller();
        break;
      case 1:
        return 0;
        break;
      case 2:
        bigger();
        break;
    }
  }
}