This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define X first
#define Y second
int n,sol;
map<pair<string,int>,int> m; //prefix, up/down, id
map<pair<string,string>,int> ob;
map<pair<string,int>,int> mf; //prefix, up/down, id
map<pair<string,string>,int> obf;
map<pair<string,string>,int> isti;
pair<string,string> Flip(string x, string y){
    return {string()+y[0]+x[0], string()+y[1]+x[1]};
}
int main(){
    cin >> n;
    for(int i = 0;i<n;i++){
        string a,b; cin >> a >> b;
        sol+=m[{a,1}]+m[{b,0}]-ob[{b,a}];
        m[{a,0}]++;
        m[{b,1}]++;
        ob[{a,b}]++;
        pair<string,string> f = Flip(a,b);
        a = f.X; b = f.Y;
        sol+=mf[{a,1}]+mf[{b,0}]-obf[{b,a}];
        mf[{a,0}]++;
        mf[{b,1}]++;
        obf[{a,b}]++;
        if(a[0]==a[1] && a[1] == b[0] && b[0] == b[1]){
            sol-=isti[{a,b}];
            isti[{a,b}]++;
        }
    }
    cout << sol;
}
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