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#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <stack>
#include "../utils.h"
class Arc {
public: Arc (std::string s, std::string t) : s(s), t(t) {}
std::string s, t;
};
class Graph {
public: Graph () { }
std::vector<std::string> nodes;
std::vector<Arc> arcs;
std::vector<std::string> star (std::string start) {
std::vector<std::string> res;
for (auto arc : arcs) {
if (arc.s == start) res.push_back(arc.t);
if (arc.t == start) res.push_back(arc.s);
}
return res;
}
};
int count (std::vector<std::string> vec, std::string str) {
return std::count(std::begin(vec), std::end(vec), str);
}
bool lower (std::string str) {
for (auto c : str) if (!islower(c)) return false;
return true;
}
bool check (std::vector<std::string> vec, std::string str, bool twice) {
if (!lower(str)) return true;
if (count(vec, str) < 1) return true;
if (twice) {
std::string flag = "";
for (auto s : vec) {
if (count(vec, s) > 1 && lower(s)) {
if (flag == "") flag = s;
else return false;
}
}
return true;
}
return false;
}
using Paths = std::vector<std::vector<std::string>>;
Paths follow (Graph G, std::vector<std::string> path, bool twice) {
auto c = path[path.size()-1];
auto star = G.star(c);
Paths paths;
if (c == "end") {
paths.push_back(path);
return paths;
}
for (auto n : star) {
if (n == "start") continue;
if (!check(path, n, twice)) continue;
std::vector<std::string> newpath = path;
newpath.push_back(n);
Paths res = follow(G, newpath, twice);
paths.insert(std::end(paths), std::begin(res), std::end(res));
}
return paths;
}
Paths search (Graph G, bool twice) {
return follow(G, std::vector<std::string> { "start" }, twice);
}
int main (int argc, char *argv[]) {
std::string raw;
std::getline(std::ifstream(argv[1]), raw, '\0');
std::vector<std::string> lines;
split(lines, raw, "\n");
Graph graph;
for (auto line : lines) {
if (line.size() == 0) continue;
std::vector<std::string> tokens;
split(tokens, line, "-");
graph.nodes.push_back(tokens[0]);
graph.nodes.push_back(tokens[1]);
graph.arcs.push_back(Arc { tokens[0], tokens[1] });
}
auto paths = search(graph, (argc > 2 ? (atoi(argv[2]) == 1) : false));
for (auto p : paths) {
for (auto s : p) {
std::cout << s << ",";
}
std::cout << std::endl;
}
std::cout << "paths: " << paths.size() << std::endl;
return 0;
}
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