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> 
#define X first
#define Y second
#define ll long long
#define pii pair<int, int>
#define pb push_back
#define vec vector
#define siz size()
#define pri(i, poc, n, pov) for(int i = (int) poc; i < (int) n; i += (int) pov)
#define od(i, poc, n, pov) for(int i = (int) poc; i > (int) n; i -= (int) pov)
using namespace std;
const ll INF = 1e18;                              
const int LOG = 20;
const int OFF = (1 << LOG);
const int MOD = 1e9 + 7;
const int lx[8] = {1, -1, 0, 0, -1, 1, 1, -1};
const int ly[8] = {0, 0, 1, -1, -1, 1, -1, 1};
const int N = 1e5 + 10;
int abs(int x){ 
	if(x < 0)
		return -x;
	return x;
}
ll a[26][26], b[26][26], c[26][26], d[26][26];
ll bc[26][26][26], cd[26][26][26], ad[26][26][26], ab[26][26][26];
ll all[26][26][26][26];
int main(){ 
	ios_base::sync_with_stdio(false); 
	cin.tie(0);
	cout.tie(0);
	setprecision(9);
	int n;
	cin >> n;
	ll ans = 0;
	pri(i, 0, n, 1){ 
		char s1, s2, s3, s4;
		cin >> s1 >> s2 >> s3 >> s4;
		int x = s1 - 'A';
		int y = s2 - 'A';
		int z = s3 - 'A';
		int w = s4 - 'A';
			
		ans += c[x][y] + d[z][x] + a[z][w] + b[y][w];
		if(y == z){
			ans -= ab[w][z][w];
			ans -= cd[x][y][x]; 
		}
		if(x == w){ 
			ans -= bc[y][w][y];
			ans -= ad[z][y][z];
		}
		if(x == w && y == z) ans += all[x][y][x][y];
		else{
			ans -= all[w][z][x][y];
			ans -= all[x][y][w][z];
		}
		a[y][x]++;
		b[x][z]++;
		c[z][w]++;
		d[w][y]++;
		ab[y][x][z]++;	
		ad[w][y][x]++;
		bc[x][z][w]++;
		cd[z][w][y]++;
		all[y][x][z][w]++;
	}
	cout << ans;
	return 0;
}
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