[training day3] delete

delete

---

Their thinking

If a number does not appear in the second or third line , Then the other column containing this number must be deleted , Violent enumeration operation is enough .

code

#include<iostream>
#include<cstdio>
using namespace std;

int n;
int a[100010];
int b[100010];
int c[100010];
int v[100010];
int s1[100010];
int s2[100010];

int main()
{
    
	cin>>n;
	for(int i=1;i<=n;i++)
		scanf("%d",&a[i]);
	for(int i=1;i<=n;i++)
		scanf("%d",&b[i]),s1[b[i]]++;
	for(int i=1;i<=n;i++)
		scanf("%d",&c[i]),s2[c[i]]++;
	int flg=1,ans=0;
	while(flg)
	{
    
		flg=0;
		for(int i=1;i<=n;i++)
			if(!v[i]&&(!s1[a[i]]||!s2[a[i]]||!s2[b[i]]||!s1[c[i]]))
				v[i]=1,s1[b[i]]--,s2[c[i]]--,flg=1,ans++;
	}
	cout<<ans<<endl;
}