first commit

2022-12-15 23:51:04 +07:00
commit 87d51fb251
292 changed files with 12623 additions and 0 deletions
@@ -0,0 +1,22 @@
+import java.util.*;
+import java.io.*;
+
+public class Main {
+    public static void main(String[] args) throws IOException, ClassNotFoundException {
+        // Scanner sc = new Scanner(new File("ONLINE.in"));
+        Scanner sc = new Scanner(System.in);
+        int n = sc.nextInt();
+        int[] ke = new int[n+1];
+        for(int i=0;i<n-1;i++){
+            int x = sc.nextInt(), y = sc.nextInt();
+            ke[x]++;
+            ke[y]++;
+        }
+        int cnt=0;
+        for(int i=1;i<=n;i++){
+            if(ke[i]>1) cnt++;
+        }
+        if(cnt>1) System.out.println("No");
+        else System.out.println("Yes");
+    }
+}