52 lines
1 KiB
C++
52 lines
1 KiB
C++
#pragma once
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#include "clusters.hpp"
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#include <vector>
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template <typename Grid>
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struct Solution {
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using Trace = std::vector<typename Grid::Position>;
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Trace current_trace;
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std::vector<Trace> solution_traces;
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};
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template <typename T>
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auto pop(std::vector<T> & v){
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v.erase(v.end()-1);
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}
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template <typename Grid, typename Rules>
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auto solve_impl(Grid const & grid, Rules const & rules, Solution<Grid> & s){
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if(grid.empty()){
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// solved path
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s.solution_traces.push_back(s.current_trace);
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return;
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}
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auto&& clusters = all_clusters(grid, rules);
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if(clusters.empty()){
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// unsolvable path
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return;
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}
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for(auto&& c : clusters){
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// remove the cluster
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s.current_trace.push_back(*c.begin());
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auto new_grid = make_empty(grid, c);
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// recurse
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solve_impl(new_grid, rules, s);
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// go on with next cluster
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pop(s.current_trace);
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}
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return;
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}
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template <typename Grid, typename Rules>
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auto solve(Grid const & grid, Rules const & rules){
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Solution<Grid> s;
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s.current_trace.reserve(10);
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solve_impl(grid, rules, s);
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return s;
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}
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