67 lines
1.6 KiB
C++
67 lines
1.6 KiB
C++
#include <algorithm>
|
|
#include <fstream>
|
|
#include <iostream>
|
|
#include <sstream>
|
|
#include <unordered_map>
|
|
#include <vector>
|
|
|
|
int q1(std::ifstream &in) {
|
|
std::vector<int> l1;
|
|
std::vector<int> l2;
|
|
|
|
// for (std::string line; std::getline(in, line);) {
|
|
// std::string left = line.substr(0, line.find(" "));
|
|
// std::string right = line.substr(line.rfind(" "));
|
|
// l1.push_back(std::stoi(left));
|
|
// l2.push_back(std::stoi(right));
|
|
// }
|
|
|
|
for (std::string line; std::getline(in, line);) {
|
|
int left, right;
|
|
std::stringstream s(line);
|
|
s >> left >> right;
|
|
l1.push_back(left);
|
|
l2.push_back(right);
|
|
}
|
|
|
|
std::sort(l1.begin(), l1.end());
|
|
std::sort(l2.begin(), l2.end());
|
|
|
|
int sum = 0;
|
|
for (int i = 0; i < l1.size(); i++) {
|
|
sum += abs(l1[i]-l2[i]);
|
|
}
|
|
return sum;
|
|
}
|
|
|
|
int q2(std::ifstream &in) {
|
|
std::vector<int> l1;
|
|
std::unordered_map<int, int> l2;
|
|
|
|
for (std::string line; std::getline(in, line);) {
|
|
std::string left = line.substr(0, line.find(" "));
|
|
std::string right = line.substr(line.rfind(" "));
|
|
l1.push_back(std::stoi(left));
|
|
l2[std::stoi(right)]++;
|
|
}
|
|
|
|
std::sort(l1.begin(), l1.end());
|
|
|
|
int sum = 0;
|
|
for (int i = 0; i < l1.size(); i++) {
|
|
sum += l1[i] * l2[l1[i]];
|
|
}
|
|
return sum;
|
|
}
|
|
|
|
int main() {
|
|
std::ifstream input("i1.txt");
|
|
std::cout << "Part 1: " << q1(input) << std::endl;
|
|
|
|
// Could re-read the file, or just seek to the beginning.
|
|
// input = std::ifstream("i1.txt");
|
|
input.clear();
|
|
input.seekg(0);
|
|
std::cout << "Part 2: " << q2(input) << std::endl;
|
|
}
|