func_code_string: #include <bits/stdc++.h>   using namespace std;   int n, m;   int state[10000];   int cnt, sum;   void dfs(int depth) {     if (depth >= m) {       for (int i = 0; i < n - 1; ++i) {         for (int j = i + 1; j < n; ++j) {           if (state[i] > state[j]) ++cnt;         }       }     } else {       for (int i = 0; i < n; ++i) {         for (int j = i; j < n; ++j) {           for (int a = i, b = j; a < b; ++a, --b) swap(state[a], state[b]);           dfs(depth + 1);           for (int a = i, b = j; a < b; ++a, --b) swap(state[a], state[b]);         }       }     }   }   int main() {     scanf( %d%d , &n, &m);     for (int i = 0; i < n; ++i) {       scanf( %d , &state[i]);     }     cnt = 0;     dfs(0);     double ans = cnt / pow(n * (n - 1) / 2 + n, m);     printf( %.12f n , ans);     return 0;   }   