func_code_string: #include <bits/stdc++.h>   using namespace std;   bool *Seive(long long n, bool *p) {     memset(p, 1, sizeof(p));     long long i, j;     for (i = 2; i <= n; i++) {       if (p[i] == 1)         for (j = i * i; j <= n; j += i) {           p[j] = 0;         }     }     p[1] = 0;     return p;   }   long long gcd(long long a, long long b) {     if (b == 0)       return a;     else       return gcd(b, a % b);   }   long long modexp(long long x, long long y) {     if (y == 0)       return 1;     else if (y % 2 == 0) {       return modexp((x * x) % (long long)998244353, y / 2);     } else {       return (x * modexp((x * x) % (long long)998244353, (y - 1) / 2)) %              (long long)998244353;     }   }   long long fact(long long n) {     long long f = 1;     for (long long i = 2; i <= n; i++) {       f = (i % (long long)998244353 * f % (long long)998244353) %           (long long)998244353;     }     return f;   }   long long nCr(long long n, long long r) {     return (fact(n) * modexp((fact(n - r) * fact(r)) % (long long)998244353,                              (long long)998244353 - 2)) %            (long long)998244353;   }   void showlist(list<int64_t> g) {     list<int64_t>::iterator it;     for (it = g.begin(); it != g.end(); ++it) cout << *it <<    ;     cout <<   n ;   }   void swap(int64_t &a, int64_t &b) {     int64_t t;     t = a;     a = b;     b = t;   }   void build(int64_t l, int64_t r, int64_t i) {     if (l == r) {     } else {       int64_t mid = (l + r) / 2;       build(l, mid, 2 * i);       build(mid + 1, r, 2 * i + 1);     }   }   void update(int64_t p, int64_t l, int64_t r, int64_t i) {     if (l == r) {     } else {       int64_t mid = (l + r) / 2;       if (p <= mid) {         update(p, l, mid, 2 * i);       } else {         update(p, mid + 1, r, 2 * i + 1);       }     }   }   void query(int64_t y, int64_t z, int64_t l, int64_t r, int64_t i) {     if (y <= l && z >= r) {     } else {       int64_t mid = (l + r) / 2;       if (z <= mid) {         query(y, z, l, mid, 2 * i);       } else if (y > mid) {         query(y, z, mid + 1, r, 2 * i + 1);       } else {         query(y, z, l, mid, 2 * i);         query(y, z, mid + 1, r, 2 * i + 1);       }     }   }   void make_set(int64_t v) {}   int64_t find_set(int64_t v) {}   void union_sets(int64_t a, int64_t b) {}   int64_t dfs(int64_t r, int64_t *d, int64_t &e, int64_t l,               vector<vector<int64_t>> &adj, int64_t *v, int64_t a[][2]) {     a[r][1] = e + d[r];     e = a[r][1];     l = e;     int64_t j = 0;     for (int64_t i = 0; i < adj[r].size(); i++) {       if (v[adj[r][i]] == 0) {         v[adj[r][i]] = 1;         a[adj[r][i]][0] = l - (j + 1);         dfs(adj[r][i], d, e, l, adj, v, a);         j++;       }     }   }   int32_t main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     int64_t n, k, i, j, w;     cin >> n >> k;     string s;     set<string> g;     for (i = 0; i < n; i++) {       cin >> s;       g.insert(s);     }     vector<string> v;     for (auto it = g.begin(); it != g.end(); it++) {       v.push_back(*it);     }     int64_t sum = 0;     for (i = 0; i < n - 2; i++) {       string q;       q = v[i];       set<string> t;       for (j = i + 1; j < n; j++) {         t.insert(v[j]);       }       for (j = i + 1; j < n; j++) {         string z;         z = v[j];         string d;         for (w = 0; w < k; w++) {           if (q[w] == z[w]) {             d += q[w];           } else {             char a;             if (q[w] ==  S  && z[w] ==  T  || z[w] ==  S  && q[w] ==  T ) {               a =  E ;             } else if (q[w] ==  E  && z[w] ==  T  || z[w] ==  E  && q[w] ==  T ) {               a =  S ;             } else if (q[w] ==  E  && z[w] ==  S  || z[w] ==  E  && q[w] ==  S ) {               a =  T ;             }             d += a;           }         }         if (t.find(d) != t.end()) {           sum++;           t.erase(d);           t.erase(z);         } else {           t.erase(z);         }       }     }     cout << sum <<   n ;     return 0;   }   