Java实现 洛谷 P2024 [NOI2001]食物链

输入输出样例

输入 #1

100 7
1 101 1
2 1 2
2 2 3
2 3 3
1 1 3
2 3 1
1 5 5

输出 #1

3

import java.util.Scanner;

public class Main {
	static int x[],sum=0;
public static void main(String[] args) {
	Scanner sc=new Scanner(System.in);
	int n=sc.nextInt();
	int m=sc.nextInt();
	x=new int[n*4];//储存祖宗,储存每个对象以及天敌,所捕食动物
	for (int i = 0; i < x.length; i++) {
		x[i]=i;
	}
	TO:
	for (int i = 0; i <m; i++) {
		int a=sc.nextInt();
		int b=sc.nextInt();
		int c=sc.nextInt();
		if(c>n||b>n){
			sum++;

			continue TO;
		}
		if(a==2){
			if(c==b){
				sum++;
				continue TO;
			}
		}
		if(a==1){
			if(find(b+n)==find(c)||find(b+2*n)==find(c)){
				sum++;
				continue TO;
			}else{
				contic(b,c);contic(b+n,c+n);contic(b+2*n,c+2*n);
			}
		}
		if(a==2){
			if(find(b)==find(c)||find(b+2*n)==find(c)){
				sum++;
				continue TO;
			}else{
				contic(b+n,c);contic(b+2*n,c+n);contic(c+2*n,b);
			}
		}
	}
	System.out.println(sum);

}
public static int find(int p){
	return x[p]==p?p:find(x[p]);
}
public static void contic(int q,int p){
	int Q=find(q);
	int P=find(p);
	if(Q==P){
		return;
	}
	x[Q]=P;

}
}