Advent Of Code 2025

day01_part1.cpp

#include <fstream>
#include <string>
#include <iostream>
#include <vector>
#include <iterator>
#include <ranges>
#include <algorithm>

using std::string, std::vector, std::plus;
using std::ifstream, std::istream_iterator, std::cout, std::endl;
using std::ranges::fold_left, std::views::all, std::views::transform;

int main()
{
    int state = 50;
    auto rotator = [&state](int i) {return !((state += 100 + i) % 100);};

    auto parse =[](const string &s) {return (s[0] == 'L' ? -1 : 1) * stoi(s.substr(1));};
    using Iter = istream_iterator<string>;
    ifstream in("1.txt");
    cout << fold_left(
        all(vector<string>{Iter{in}, Iter{}}) |
        transform(parse) |
        transform(rotator), 0, plus<>{}
    ) << endl;
}