func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m;   char A[200006];   int S[200006], T[200006];   void solve() {     cin >> n >> m;     scanf( %s , A + 1);     long long re = 0;     for (int i = (1), iend = (n); i <= iend; ++i) {       S[i] = (A[i] != A[i + 1]) + S[i - 1];       if (i >= 2 && A[i] == A[i - 2])         T[i] = T[i - 1] + 1;       else if (i >= 2)         T[i] = 2;       else         T[i] = 1;     }     for (int r = (1), rend = (n); r <= rend; ++r) {       if (A[r] != A[r - 1]) re += (m - 1) * 1ll * (r - 1);       re += m - 1;       re += S[r - 1] * 1ll * (m - 1);       if (A[r] != A[r - 1]) re -= T[r] - 1;     }     cout << re << endl;   }   signed main() { solve(); }   