CPSC 120 Example calculating a 15% tip.

cpsc120_tip.cc

// Gist https://gist.github.com/f6d31d8630589c2e8986de8ce6238350

#include <iostream>

int main(int argc, char const *argv[]) {
  // Constant tip rate of 15% expressed as a decimal of 0.15
  const double kTipRate{0.15};
  std::cout << "What was the bill's sum? ";
  double bill;
  std::cin >> bill;
  double tip_amount{bill * kTipRate};
  double total_bill{bill + tip_amount};
  std::cout << "The bill is $" << bill << " and " << kTipRate * 100.0
            << "% tip is $" << tip_amount << " so the total bill is $"
            << total_bill << ".\n";
  return 0;
}