[training day3] delete [simulation]

Ideas ：

Direct simulation , Delete the impossible column , Then there is the answer

$code$

#include<iostream>
#include<cstdio>

using namespace std;

const int MAXN = 1e5 + 10;

int n, tot;
int a[MAXN], b[MAXN], c[MAXN], d[MAXN], e[MAXN];
bool v[MAXN];

int main() {
    
	scanf("%d", &n);
	for(int i = 1; i <= n; i ++) scanf("%d", &a[i]);
	for(int i = 1; i <= n; i ++) scanf("%d", &b[i]), d[b[i]] ++;
	for(int i = 1; i <= n; i ++) scanf("%d", &c[i]), e[c[i]] ++;
	bool flag = 0;
	while(!flag) {
    
		flag = 1;
		for(int i = 1; i <= n; i ++)
			if(!v[i] && (d[a[i]] == 0 || e[a[i]] == 0)) {
    
				v[i] = 1;
				d[b[i]] --;
				e[c[i]] --;
				tot ++;
				flag = 0;
			}
	}
	printf("%d", tot);
	return 0;
}