[BOJ] 군사이동 / 골드3

Author: 최재익

jaeik/week9/군사이동/BOJ_11085.java

@@ -0,0 +1,64 @@
+package week9.군사이동;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.Arrays;
+import java.util.PriorityQueue;
+import java.util.StringTokenizer;
+
+public class BOJ_11085 {
+    static int[] parent;
+    static int p, w, c, v;
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+
+        p = Integer.parseInt(st.nextToken());
+        w = Integer.parseInt(st.nextToken());
+
+        st = new StringTokenizer(br.readLine());
+        c = Integer.parseInt(st.nextToken());
+        v = Integer.parseInt(st.nextToken());
+
+        parent = new int[p+1];
+        for(int i=1; i<=p; i++){
+            parent[i] = i;
+        }
+        PriorityQueue<int[]> priorityQueue = new PriorityQueue<>(((o1, o2) -> o2[2]-o1[2]));
+        for(int i=0; i<w; i++){
+            priorityQueue.add(Arrays.stream(br.readLine().split(" ")).mapToInt(Integer::parseInt).toArray());
+        }
+
+        int result = 0;
+        while(!priorityQueue.isEmpty()){
+            int[] now = priorityQueue.poll();
+            int start = now[0];
+            int end = now[1];
+            int width = now[2];
+
+            union(start, end);
+
+            if(find(c)==find(v)){
+                result = width;
+                break;
+            }
+        }
+
+        System.out.println(result);
+    }
+
+    static int find(int x){
+        if(x==parent[x])return x;
+        return parent[x]=find(parent[x]);
+    }
+
+    static void union(int x, int y){
+        x = find(x);
+        y = find(y);
+
+        if(x==y)return;
+
+        parent[y] = x;
+    }
+}