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#include <filesystem>
#include <fstream>
#include <iostream>
#include <map>
#include <set>
#include <vector>
using namespace std;
namespace {
vector<int>
read_lines(const filesystem::path& filename)
{
ifstream file{ filename };
vector<int> lines;
for ( int value{}; file >> value; ) {
lines.emplace_back(value);
}
return lines;
}
void
distribute(vector<int>& values)
{
auto iter = ranges::max_element(values);
auto max_value = *iter;
*iter = 0;
while ( max_value-- > 0 ) {
++iter;
if ( iter == values.end() ) {
iter = values.begin();
}
*iter += 1;
}
}
void
part1(vector<int> values)
{
set<vector<int>> seen;
for ( int step = 0;; ++step ) {
if ( seen.contains(values) ) {
cout << "Part1: " << step << '\n';
return;
}
seen.insert(values);
distribute(values);
}
}
void
part2(vector<int> values)
{
map<vector<int>, int> seen;
for ( int step = 0;; ++step ) {
if ( seen.contains(values) ) {
cout << "Part2: " << step - seen.at(values) << '\n';
return;
}
seen.emplace(values, step);
distribute(values);
}
}
} // namespace
int
main()
{
auto values = read_lines("data/day06.txt");
part1(values);
part2(values);
}
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