View Code of Problem 131

import java.util.*;
public class Main {
	 public static void main(String[] args) {
		 Scanner in = new Scanner(System.in);
		 while(in.hasNext()) {
			 int n = in.nextInt();
			 int m = in.nextInt();
			 int[][] link = new int[n][n];
			 for(int i =0;i<m;i++) {
				 int a=in.nextInt()-1;
				 int b=in.nextInt()-1;
				 link[a][b]=1;
			 }
			 boolean bl=false;
			 for(int i =0;i<n;i++) {
				 if(ifcir(link,i,0,n)) {
					 bl=true;
				 }
			 }
			 if(bl) {
				 System.out.println("ERROR");
			 }else {
				 System.out.println("RIGHT");
			 }
		 }
	 }
	 public static boolean ifcir(int[][] link,int loc,int t,int n) {
		 if(t>=n) {
			 return true;
		 }else {
			 for(int i =0;i<link[loc].length;i++) {
				 if(link[loc][i]!=0) {
					 if(ifcir(link,i,t+1,n)) {
						 return true;
					 }
				 }
			 }
			 return false;
		 }
	 }
}