[20250204] BOJ / 플래3 / A Journey to Greece / 권혁준

Author: oncsr

khj20006/202502/04 BOJ A Journey to Greece.md

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+```java
+
+import java.util.*;
+import java.io.*;
+
+class Main {
+	
+	// IO field
+	static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+	static BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+	static StringTokenizer st;
+
+	static void nextLine() throws Exception {st = new StringTokenizer(br.readLine());}
+	static int nextInt() {return Integer.parseInt(st.nextToken());}
+	static long nextLong() {return Long.parseLong(st.nextToken());}
+	static void bwEnd() throws Exception {bw.flush();bw.close();}
+	
+	// Additional field
+	static int INF = (int)1e9 + 1;
+	static int N, P, M, G, T;
+	static int[] p;
+	static int[] num;
+	static List<int[]>[] V;
+	static int[][] dist;
+	static int[][] cost;
+	static int[][][] dp;
+	
+	static void sizeInitialize() {
+		p = new int[P+1];
+		num = new int[N+1];
+		V = new ArrayList[N+1];
+		for(int i=0;i<=N;i++) V[i] = new ArrayList<>();
+		dist = new int[P+1][N+1];
+		cost = new int[P+1][P+1];
+		dp = new int[P+1][2][1<<(P+1)];
+		for(int i=0;i<=P;i++) for(int j=0;j<2;j++) Arrays.fill(dp[i][j], INF);
+	}
+	
+	static void input() throws Exception {
+		
+		nextLine();
+		N = nextInt();
+		P = nextInt();
+		M = nextInt();
+		G = nextInt();
+		T = nextInt();
+		
+		sizeInitialize();
+		
+		for(int i=1;i<=P;i++) {
+			nextLine();
+			int a = nextInt(), b = nextInt();
+			G -= b;
+			p[i] = a;
+			num[p[i]] = i;
+		}
+		
+		for(int i=0;i<M;i++) {
+			nextLine();
+			int a = nextInt(), b = nextInt(), c = nextInt();
+			V[a].add(new int[] {b,c});
+			V[b].add(new int[] {a,c});
+		}
+		
+	}
+	
+	static void dijk(int s) {
+		Arrays.fill(dist[s], INF);
+		
+		PriorityQueue<int[]> PQ = new PriorityQueue<>((a,b) -> a[0]-b[0]);
+		PQ.offer(new int[] {0,p[s]});
+		dist[s][p[s]] = 0;
+		while(!PQ.isEmpty()) {
+			int[] now = PQ.poll();
+			int d = now[0], n = now[1];
+			if(d > dist[s][n]) continue;
+			for(int[] x : V[n]) {
+				int nx = x[0], c = x[1];
+				if(dist[s][nx] > d + c) {
+					dist[s][nx] = d+c;
+					PQ.offer(new int[] {d+c,nx});
+				}
+			}
+		}
+		
+	}
+	
+	static void constructNewGraph() {
+		for(int i=0;i<=P;i++) for(int j=0;j<=P;j++) cost[i][j] = dist[i][p[j]];
+	}
+	
+	static int solve(int n, int x, int k) {
+		if(dp[n][x][k] != INF) return dp[n][x][k];
+		int prev = k ^ (1<<n);
+		for(int i=0;i<=P;i++) {
+			if((prev & (1<<i)) == 0) continue;
+			// no taxi
+			dp[n][x][k] = Math.min(dp[n][x][k], solve(i,x,prev) + cost[i][n]);
+			// can taxi
+			if(x == 1) dp[n][x][k] = Math.min(dp[n][x][k], solve(i,0,prev) + T);
+		}
+		
+		return dp[n][x][k];
+	}
+
+	public static void main(String[] args) throws Exception {
+
+		input();
+		
+		for(int i=0;i<=P;i++) dijk(i);
+		
+		constructNewGraph();
+		
+		for(int i=1;i<=P;i++) {
+			dp[i][0][1<<i] = cost[0][i];
+			dp[i][1][1<<i] = T;
+		}
+		int withoutTaxi = solve(0,0,(1<<(P+1))-1);
+		int withTaxi = solve(0,1,(1<<(P+1))-1);
+		
+		if(withoutTaxi <= G) bw.write("possible without taxi");
+		else if(withTaxi <= G) bw.write("possible with taxi");
+		else bw.write("impossible");
+		
+		
+		
+		bwEnd();
+	}
+
+}
+
+```