Merge pull request #879 from AlgorithmWithGod/khj20006

[20250912] BOJ / P5 / 밤편지 / 권혁준

Author: ShinHeeEul

khj20006/202509/12 BOJ P5 밤편지.md

@@ -0,0 +1,127 @@
+```java
+import java.io.*;
+import java.util.*;
+
+class IOController {
+	BufferedReader br;
+	BufferedWriter bw;
+	StringTokenizer st;
+
+	public IOController() {
+		br = new BufferedReader(new InputStreamReader(System.in));
+		bw = new BufferedWriter(new OutputStreamWriter(System.out));
+		st = new StringTokenizer("");
+	}
+
+	String nextLine() throws Exception {
+		String line = br.readLine();
+		st = new StringTokenizer(line);
+		return line;
+	}
+
+	String nextToken() throws Exception {
+		while (!st.hasMoreTokens())
+			nextLine();
+		return st.nextToken();
+	}
+
+	int nextInt() throws Exception {
+		return Integer.parseInt(nextToken());
+	}
+
+	long nextLong() throws Exception {
+		return Long.parseLong(nextToken());
+	}
+
+	double nextDouble() throws Exception {
+		return Double.parseDouble(nextToken());
+	}
+
+	void close() throws Exception {
+		bw.flush();
+		bw.close();
+	}
+
+	void write(String content) throws Exception {
+		bw.write(content);
+	}
+
+}
+
+public class Main {
+
+	static IOController io;
+
+	//
+
+	static final int INF = 715827881;
+
+	static int N, M;
+	static int[][] cost, dist, val, queries;
+
+	public static void main(String[] args) throws Exception {
+
+		io = new IOController();
+
+		N = io.nextInt();
+		M = io.nextInt();
+		cost = new int[N+1][N+1];
+		dist = new int[N+1][N+1];
+		val = new int[N+1][N+1];
+		for(int i=1;i<=N;i++) for(int j=1;j<=N;j++) {
+			cost[i][j] = io.nextInt();
+			if(cost[i][j] == 0 && i != j) cost[i][j] = INF;
+			if(i != j) {
+				dist[i][j] = INF;
+				val[i][j] = INF;
+			}
+		}
+
+		queries = new int[M][];
+		for(int i=0;i<M;i++) queries[i] = new int[]{io.nextInt(),io.nextInt(),io.nextInt(),i};
+		Arrays.sort(queries, (a,b) -> a[0]-b[0]);
+
+		int limit = 1;
+		int[] ans = new int[M];
+		for(int[] query : queries) {
+			int c = query[0], s = query[1], e = query[2], i = query[3];
+			while(limit < c) {
+				for(int x=limit;x<=N;x++) for(int y=x;y<=N;y++) for(int k=1;k<limit;k++) {
+					val[x][y] = Math.min(val[x][y], cost[x][limit] + dist[limit][k] + cost[k][y]);
+					val[x][y] = Math.min(val[x][y], cost[x][k] + dist[k][limit] + cost[limit][y]);
+				}
+				for(int k=1;k<=limit;k++) {
+					dist[limit][k] = Math.min(dist[limit][k], cost[limit][k]);
+					dist[k][limit] = Math.min(dist[k][limit], cost[k][limit]);
+				}
+				for(int j=1;j<=limit;j++) for(int k=1;k<=limit;k++) dist[j][k] = Math.min(dist[j][k], dist[j][limit] + dist[limit][k]);
+				limit++;
+			}
+			if(s == e) ans[i] = 0;
+			else {
+				if(s > e) {
+					int t = s;
+					s = e;
+					e = t;
+				}
+				if(s < c && e < c) ans[i] = dist[s][e] == INF ? -1 : dist[s][e];
+				else if(s < c) {
+					int res = INF;
+					for(int k=1;k<c;k++) res = Math.min(res, dist[s][k] + cost[k][e]);
+					ans[i] = res == INF ? -1 : res;
+				}
+				else {
+					if(val[s][e] == INF) ans[i] = cost[s][e] == INF ? -1 : cost[s][e];
+					else ans[i] = val[s][e] == INF ? -1 : val[s][e];
+				}
+			}
+		}
+
+		for(int i=0;i<M;i++) io.write(ans[i] + "\n");
+
+		io.close();
+
+	}
+
+}
+```