[coci2011]友好数对 容斥

#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cstdlib>
#include<ctime>
#include<vector>
#include<algorithm>
#include<queue>
#include<map>
using namespace std;
#define LL long long
int n;
LL x=0;
int b[1<<11],c[1<<11];
void init(){
    cin>>n;
    int y,p;
    for(int i=1;i<=n;i++){
        scanf("%I64d",&x);
        p=0;
        while(x!=0){
            y=x%10;
            x/=10;
            p=p|(1<<y);
        }
        b[p]++;
    }
}
LL col(LL x){return x*(x-1)/2;}
void work(){
    for(int i=1;i<1<<10;i++)
        for(int j=1;j<1<<10;j++)
            if((i|j)==i)c[j]+=b[i];
    int sum=0;
    LL ans=0;
    for(int i=1;i<1<<10;i++){
        sum=0;
        for(int j=0;j<10;j++){
            if(i&(1<<j))sum++;
        }
        if(sum%2)ans+=col(c[i]);
        else ans-=col(c[i]);
    }
    cout<<ans<<endl;
}
int main(){
    //freopen("1.in","r",stdin);
    //freopen("1.out","w",stdout);
    init();
    work();
}