Add day 14 solution for part 1

day14/Makefile

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+CC=g++
+BIN_NAME=day14
+CCFLAGS=-o $(BIN_NAME) -g -std=c++17
+LDFLAGS=-lfolly
+
+.PHONY: all, clean
+
+all: $(BIN_NAME)
+
+clean:
+	rm -f $(BIN_NAME)
+
+$(BIN_NAME): day14.cpp
+	$(CC) $(CCFLAGS) $(LDFLAGS) day14.cpp
+

day14/day14.cpp

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+#include <folly/String.h>
+
+#include <algorithm>
+#include <cassert>
+#include <charconv>
+#include <fstream>
+#include <iostream>
+#include <map>
+#include <numeric>
+#include <regex>
+#include <vector>
+
+constexpr char IGNORE_CHAR = 'X';
+constexpr auto MASK_PATTERN = R"(mask = ([X0-9]+))";
+constexpr auto MEM_PATTERN = R"(mem\[(\d+)\] = (\d+))";
+
+class InstructionBlock {
+ public:
+	InstructionBlock(std::string mask, std::vector<std::pair<int, int>> storeInstructions)
+		: mask(mask), storeInstructions(storeInstructions) {
+	}
+
+	// We are dealing with a 36 bit numebr so we must use a long long to guarantee we can fit it
+	long long maskNumber(long long num) const {
+		long long res = num;
+		for (int i = 0; i < this->mask.size(); i++) {
+			char maskChar = this->mask.at(this->mask.size() - i - 1);
+			if (maskChar == IGNORE_CHAR) {
+				continue;
+			} else if (maskChar == '0') {
+				res &= ~(1LL << i);
+			} else if (maskChar == '1') {
+				res |= (1LL << i);
+			}
+		}
+
+		return res;
+	}
+
+	const std::vector<std::pair<int, int>> &getStoreInstructions() const {
+		return this->storeInstructions;
+	}
+
+ private:
+	std::string mask;
+	std::vector<std::pair<int, int>> storeInstructions;
+};
+
+std::vector<std::string> readInput(const std::string &filename) {
+	std::vector<std::string> input;
+	std::string line;
+	std::ifstream file(filename);
+	while (std::getline(file, line)) {
+		input.push_back(line);
+	}
+
+	return input;
+}
+
+std::vector<InstructionBlock> parseInput(const std::vector<std::string> &input) {
+	std::vector<InstructionBlock> blocks;
+	std::regex maskExpression(MASK_PATTERN);
+	std::regex memExpression(MEM_PATTERN);
+	std::string currentMask;
+	std::vector<std::pair<int, int>> currentStoreInstructions;
+	for (auto it = input.cbegin(); it != input.cend(); it++) {
+		auto line = *it;
+		std::smatch matches;
+		if (std::regex_match(line, matches, maskExpression)) {
+			// We don't want to emplace on the first mask we find
+			if (it != input.cbegin()) {
+				blocks.emplace_back(currentMask, currentStoreInstructions);
+				currentStoreInstructions.clear();
+			}
+
+			currentMask = matches[1];
+		} else if (std::regex_match(line, matches, memExpression)) {
+			int address = std::stoi(matches[1]);
+			int value = std::stoi(matches[2]);
+			currentStoreInstructions.emplace_back(address, value);
+		}
+	}
+
+	// Put in the last one we've found
+	blocks.emplace_back(currentMask, currentStoreInstructions);
+
+	return blocks;
+}
+
+long long part1(const std::vector<InstructionBlock> &instructions) {
+	std::unordered_map<int, long long> memory;
+	for (const InstructionBlock &instruction : instructions) {
+		for (const std::pair<int, int> &storeInstruction : instruction.getStoreInstructions()) {
+			auto maskedStorage = instruction.maskNumber(storeInstruction.second);
+			memory[storeInstruction.first] = maskedStorage;
+		}
+	}
+
+	return std::accumulate(
+		memory.cbegin(), memory.cend(), 0LL, [](long long total, std::pair<int, long long> memoryItem) {
+			return total + memoryItem.second;
+		});
+}
+
+int main(int argc, char *argv[]) {
+	if (argc != 2) {
+		std::cerr << argv[0] << " <input_file>" << std::endl;
+		return 1;
+	}
+
+	auto input = readInput(argv[1]);
+	auto parsedInput = parseInput(input);
+
+	std::cout << part1(parsedInput) << std::endl;
+}