boj 1865 웜홀

Author: emost22

Bellman-Ford/1865.cpp

@@ -0,0 +1,76 @@
+#include <iostream>
+#include <algorithm>
+#include <vector>
+#define INF 1000000000
+using namespace std;
+
+vector<pair<int, int> > weight[501];
+bool cyclechk;
+int edge[501][501];
+int d[501], N, M, W, s, e, t;
+
+void init() {
+	d[1] = 0;
+	for (int i = 2; i <= N; i++) {
+		d[i] = INF;
+	}
+	for (int i = 1; i <= N; i++) {
+		for (int j = 1; j <= N; j++) {
+			edge[i][j] = INF;
+		}
+	}
+}
+
+int main() {
+	cin.tie(NULL); cout.tie(NULL);
+	ios::sync_with_stdio(false);
+
+	int Testcase;
+	cin >> Testcase;
+	while (Testcase--) {
+		cin >> N >> M >> W;
+		init();
+
+		for (int i = 0; i < M; i++) {
+			cin >> s >> e >> t;
+			
+			edge[s][e] = min(edge[s][e], t);
+			edge[e][s] = min(edge[e][s], t);
+		}
+		for (int i = 0; i < W; i++) {
+			cin >> s >> e >> t;
+			
+			edge[s][e] = min(edge[s][e], -t);
+		}
+
+		for (int i = 1; i <= N; i++) {
+			for (int j = 1; j <= N; j++) {
+				if (edge[i][j] < INF) {
+					weight[i].push_back({ j, edge[i][j] });
+				}
+			}
+		}
+
+		for (int i = 1; i <= N; i++) {
+			for (int j = 1; j <= N; j++) {
+				for (int k = 0; k < weight[j].size(); k++) {
+					int next = weight[j][k].first;
+					int dis = weight[j][k].second;
+
+					if (d[next] > d[j] + dis) {
+						d[next] = d[j] + dis;
+						if (i == N) cyclechk = true;
+					}
+				}
+			}
+		}
+
+		if (cyclechk) cout << "YES\n";
+		else cout << "NO\n";
+
+		cyclechk = false;
+		for (int i = 1; i <= N; i++) weight[i].clear();
+	}
+
+	return 0;
+}