Merge pull request #2650 from hakyurxinf/master

Create 107寻找存在的路径Java代码

107寻找存在的路径Java代码

@@ -0,0 +1,56 @@
+JAVA:
+
+```Java
+
+import java.util.*;
+ 
+public class Main{
+    public static void main(String[] args) {
+        int N, M;
+        Scanner scanner = new Scanner(System.in);
+        N = scanner.nextInt();
+        M = scanner.nextInt();
+        DisJoint disJoint = new DisJoint(N + 1);
+        for (int i = 0; i < M; ++i) {
+            disJoint.join(scanner.nextInt(), scanner.nextInt());
+        }
+        if(disJoint.isSame(scanner.nextInt(), scanner.nextInt())) {
+            System.out.println("1");
+        } else {
+            System.out.println("0");
+        }
+    }
+ 
+}
+
+//并查集模板
+class DisJoint{
+    private int[] father;
+ 
+    public DisJoint(int N) {
+        father = new int[N];
+        for (int i = 0; i < N; ++i){
+            father[i] = i;
+        }
+    }
+ 
+    public int find(int n) {
+        return n == father[n] ? n : (father[n] = find(father[n]));
+    }
+ 
+    public void join (int n, int m) {
+        n = find(n);
+        m = find(m);
+        if (n == m) return;
+        father[m] = n;
+    }
+ 
+    public boolean isSame(int n, int m){
+        n = find(n);
+        m = find(m);
+        return n == m;
+    }
+ 
+}
+
+```