func_code_string: #include <bits/stdc++.h>   using namespace std;   void getint(int &v) {     char ch, fu = 0;     for (ch =  * ; (ch <  0  || ch >  9 ) && ch !=  - ; ch = getchar())       ;     if (ch ==  - ) fu = 1, ch = getchar();     for (v = 0; ch >=  0  && ch <=  9 ; ch = getchar()) v = v * 10 + ch -  0 ;     if (fu) v = -v;   }   int n, m, ans, a[444][444], f[444][444], p[401][160001];   int main() {     cin >> n >> m;     for (int i = 1; i <= n; ++i)       for (int j = 1; j <= m; ++j) getint(a[i][j]);     for (int i = 1; i <= n; ++i) {       for (int len = 1; len <= m; ++len)         for (int l = 1; l <= m - len + 1; ++l) {           int r = l + len - 1;           if (len > 1) {             f[l][r] = max(f[l][r], max(f[l + 1][r], f[l][r - 1]));             f[l][r] = max(f[l][r], p[r][a[i][l]]);             f[l][r] = max(f[l][r], p[l][a[i][r]]);             if (a[i][l] == a[i][r]) f[l][r] = i;           } else {             f[l][r] = max(f[l][r], p[l][a[i][l]]);           }           ans = max(ans, (i - f[l][r]) * (r - l + 1));         }       for (int j = 1; j <= m; ++j) p[j][a[i][j]] = i;     }     cout << ans << endl;     return 0;   }   