#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<cstdlib>
#include<ctime>
#include<iomanip>
using namespace std;
int str(string s1, string s2){
    if (s1.size()==s2.size()){
        if (s1==s2)return 0;
        if (s1<s2)return 1;
        else return -1;
    }
    if (s1.size() < s2.size()) return 1;
    else return -1;
}
int main(){
    int n,ans=0;
    string k;
    cin>>n>>k;
    string a[n];
    for(int i=0;i<n;i++){
        cin>>a[i];
    }
    sort(a,a+n);
    int l=0,r=n-1;
    while (l<=r){
        if(str(a[l]+a[r],k)==0){
            ans+=r-l;
            l++;
            r--;
        }
        if(str(a[l]+a[r],k)==1){
            ans+=r-l;
            l++;
        }
        else r--;
    }
    l=0;r=n-1;
    while (l<=r){
        if(str(a[r]+a[l],k)==0){
            ans+=r-l;
            l++;
            r--;
        }
        if(str(a[r]+a[l],k)==1){
            ans+=r-l;
            l++;
        }
        else r--;
    }
    cout<<ans;
    return 0;
}

到底怎么了？！硬控我调了一小时