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#include <tuple>
#include <iostream>
#include <fstream>
#include <string>
#include <sstream>
#include <stack>
#include <cmath>
#include <array>
#include <algorithm>
#include <cstdint>
#include <vector>
using stack_type = std::stack<char>;
enum PROBLEM
{
PROBLEM_1 = 1,
PROBLEM_2 = 2
};
std::tuple<std::vector<stack_type>, int> build_stacks(std::vector<std::string> &lines)
{
int num_stacks = std::ceil(lines[0].size() / 4.0);
std::vector<stack_type> stacks(num_stacks);
std::vector<int> stack_positions(num_stacks, 0);
int lines_of_stacks = 0;
for (std::string line : lines)
{
char l = '1';
for (int i = 0; i < line.size(); ++i)
if (line[i] == l)
{
stack_positions[l - '1'] = i;
l++;
}
if (l == num_stacks + '1')
break;
lines_of_stacks++;
}
for (int i = lines_of_stacks - 1; i >= 0; i--)
for (int j = 0; j < num_stacks; ++j)
if (lines[i][stack_positions[j]] != ' ')
stacks[j].push(lines[i][stack_positions[j]]);
return std::make_tuple(stacks, lines_of_stacks);
}
std::string solve(std::vector<stack_type> &stacks, std::vector<std::string> &lines, int start_from, PROBLEM problem)
{
stack_type curr;
for (auto line = lines.begin() + start_from; line != lines.end(); ++line)
{
std::istringstream iss(*line);
std::string word;
int from = 0, to = 0, amount = 0;
while (iss >> word >> amount >> word >> from >> word >> to)
;
if (problem == PROBLEM_1)
for (int i = 0; i < amount; ++i)
{
stacks[to - 1].push(stacks[from - 1].top());
stacks[from - 1].pop();
}
else
{
for (int i = 0; i < amount; ++i)
{
curr.push(stacks[from - 1].top());
stacks[from - 1].pop();
}
for (int i = 0; i < amount; ++i)
{
stacks[to - 1].push(curr.top());
curr.pop();
}
}
}
std::string result;
for (auto &stack : stacks)
result += stack.top();
return result;
}
int main()
{
std::ifstream input("input");
std::vector<std::string> lines;
for (std::string line; std::getline(input, line);)
lines.push_back(line);
auto [stacks, start_from] = build_stacks(lines);
std::cout << "Solve 1: " << solve(stacks, lines, start_from + 1, PROBLEM_1) << std::endl;
auto [stacks2, start_from2] = build_stacks(lines);
std::cout << "Solve 2: " << solve(stacks2, lines, start_from2 + 1, PROBLEM_2) << std::endl;
return 0;
}
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