Advent-of-Code/2022/2/main.cpp

89 lines
1.3 KiB
C++

#include <fstream>
#include <iostream>
#include <string>
enum RPS {
Rock = 1,
Paper,
Scissors,
};
RPS ToRPS(char c)
{
if(c == 'A' || c == 'X')
return RPS::Rock;
else if(c == 'B' || c == 'Y')
return RPS::Paper;
else if(c == 'C' || c == 'Z')
return RPS::Scissors;
std::cerr << "BAD DATA '" << c << "'." << std::endl;
exit(-1);
}
int RPSScore(RPS rps)
{
switch(rps)
{
case RPS::Rock:
return 1;
case RPS::Paper:
return 2;
case RPS::Scissors:
return 3;
}
}
bool Won(RPS us, RPS them)
{
if(us == RPS::Rock && them == RPS::Scissors)
return true;
else if(us == RPS::Paper && them == RPS::Rock)
return true;
else if(us == RPS::Scissors && them == RPS::Paper)
return true;
return false;
}
int Points(RPS us, RPS them)
{
int rtn = 0;
// score our play:
rtn += RPSScore(us);
// tie:
if(us == them)
return rtn + 3;
// win:
if(Won(us, them))
return rtn + 6;
// loss:
return rtn;
}
int main()
{
std::ifstream ifs("data.txt");
if(!ifs.is_open())
{
std::cerr << "Missing data.txt." << std::endl;
return -1;
}
unsigned long total = 0;
for(std::string line; std::getline(ifs, line); )
{
char them = line[0];
char us = line[2];
total += Points(ToRPS(us), ToRPS(them));
}
std::cout << "Total: " << total << std::endl;
return 0;
}