#include <bits/stdc++.h> #define al int #define pb push_back #define f first #define s second #define ap cout #define ak "\n" #define all(x) x.begin(),x.end() #define ok cout << __LINE__ << "| "<< "----------OK--------- -----" << endl; #define deb(x) cout << __LINE__ << "| "<< #x << " = " << x<< endl; #define fast ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0); #define af(x) ap<<x; #define ai(x) af((x ? out[1] : out[0])) #define cin(n,b) for(al i=1;i<=n;i++)cin>>b[i]; using namespace std; const al nn=2e6+9; const string out[2]={"NO","YES"}; al n,d,res,ind; string s[nn]; vector<string>a[20] ; vector<char> c[20]; void tp(){ cin>>n>>d; for(al i=1;i<=n;i++){ cin>>s[i]; s[i]="$"+s[i]; } if(d>=1){ for(al i=1;i<=n;i++){ for(al j=1;j<=4;j++){ string t; c[j].pb(s[i][j]); for(al k=1;k<=4;k++){ if(j!=k){ t+=s[i][k]; } } a[j].pb(t); } } for(al i=1;i<=4;i++){ for(al j=1;j<=4;j++){ for(al k=j+1;k<=4;k++){ if(a[i][j]==a[i][k] and c[i][j]!=c[i][k])res++; } } } // for(al i=1;i<=n;i++){ // deb(i<<" suiii "); // for(auto j:a[i]){ // deb(j); // } // deb("alonnee ") // for(auto j:c[i]){ // deb(j); // } // } af(res); } } signed main(){ fast; al tt=1; //cin>>tt; while(tt--){ tp(); ap<<ak; } }