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#include <fstream>
#include <iostream>
#include <map>
#include <vector>
#define INF 9999999
using namespace std;
template <class H>
class Graph {
public:
Graph<H>*
add_node(H u)
{
auto it = nodes_.find(u);
if (it == nodes_.end()) {
nodes_.insert({ u, vector<pair<H, int>>() });
size_++;
}
return this;
}
Graph<H>*
add_edge(H u, H v, int w)
{
auto i = nodes_.find(u);
auto j = nodes_.find(v);
if (i != nodes_.end() && j != nodes_.end()) {
nodes_[u].push_back({ v, w });
edges_.push_back({ u, v, w });
}
return this;
}
void
bellmanford(H s, H r, ostream& out)
{
map<H, int> dist;
map<H, pair<H, int>> p;
for (const auto& it : nodes_) {
dist.insert({ it.first, INF });
}
dist[s] = 0;
for (size_t i = 0; i < size_; ++i) {
for (const auto& e : edges_) {
auto u = get<0>(e);
auto v = get<1>(e);
auto w = get<2>(e);
if (dist[u] != INF && dist[u] + w < dist[v]) {
dist[v] = dist[u] + w;
p[v] = make_pair(u, dist[v]);
}
}
}
for (size_t i = 0; i < size_; ++i) {
for (const auto& e : edges_) {
auto u = get<0>(e);
auto v = get<1>(e);
auto w = get<2>(e);
if (dist[u] != INF && dist[u] + w < dist[v]) {
out << "undef." << endl;
return;
}
}
}
if (p.find(r) == p.end()) {
out << "inf." << endl;
return;
} else {
out << p[r].second << endl;
}
}
private:
// `nodes_` is map which has the node as key and the edges as value.
// eg:
// nodes_[0] = [[1, 300]];
// there is an edge 0<->1 with 300 as weight
map<H, vector<pair<H, int>>> nodes_;
vector<tuple<H, H, int>> edges_;
size_t size_ { 0 };
};
int
main(int argc, char** argv)
{
int ts = (argc > 1) ? stoi(argv[1]) : 100;
int n, m;
string tp;
string ch;
ifstream fin("input.txt");
ofstream fout("output.txt");
for (int i = 0; i < ts; ++i) {
fin >> n >> m >> tp;
if (tp == "int") {
Graph<int>* g = new Graph<int>();
int k, n1, n2, s, r;
int w;
for (int j = 0; j < n; ++j) {
fin >> k;
g->add_node(k);
}
for (int j = 0; j < m; ++j) {
fin >> ch;
n1 = stoi(ch.substr(1, ch.length()));
fin >> n2;
fin >> ch;
w = stoi(ch.substr(0, ch.length() - 1));
g->add_edge(n1, n2, w);
}
fin >> s >> r;
g->bellmanford(s, r, fout);
delete g;
} else if (tp == "double") {
Graph<int>* g = new Graph<int>();
double k, n1, n2, s, r;
int w;
for (int j = 0; j < n; ++j) {
fin >> k;
g->add_node(k * 10);
}
for (int j = 0; j < m; ++j) {
fin >> ch;
n1 = stod(ch.substr(1, ch.length()));
fin >> n2;
fin >> ch;
w = stoi(ch.substr(0, ch.length() - 1));
g->add_edge(n1 * 10, n2 * 10, w);
}
fin >> s >> r;
g->bellmanford(s * 10, r * 10, fout);
delete g;
}
}
fin.close();
fout.close();
return 0;
}
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