CF407D.Largest Submatrix 3

普及/提高-

通过率：0%

AC君温馨提醒

该题目为【codeforces】题库的题目，您提交的代码将被提交至codeforces进行远程评测，并由ACGO抓取测评结果后进行展示。由于远程测评的测评机由其他平台提供，我们无法保证该服务的稳定性，若提交后无反应，请等待一段时间后再进行重试。

题目描述

You are given matrix $a$ of size $n×m$ , its elements are integers. We will assume that the rows of the matrix are numbered from top to bottom from 1 to $n$ , the columns are numbered from left to right from 1 to $m$ . We will denote the element on the intersecting of the $i$ -th row and the $j$ -th column as $a_{ij}$ .

We'll call submatrix $i_{1},j_{1},i_{2},j_{2}$ $(1<=i_{1}<=i_{2}<=n; 1<=j_{1}<=j_{2}<=m)$ such elements $a_{ij}$ of the given matrix that $i_{1}<=i<=i_{2}$ AND $j_{1}<=j<=j_{2}$ . We'll call the area of the submatrix number $(i_{2}-i_{1}+1)·(j_{2}-j_{1}+1)$ . We'll call a submatrix inhomogeneous, if all its elements are distinct.

Find the largest (in area) inhomogenous submatrix of the given matrix.

输入格式

The first line contains two integers $n$ , $m$ ( $1<=n,m<=400$ ) — the number of rows and columns of the matrix, correspondingly.

Each of the next $n$ lines contains $m$ integers $a_{ij}$ ( $1<=a_{ij}<=160000$ ) — the elements of the matrix.

输出格式

Print a single integer — the area of the optimal inhomogenous submatrix.

输入输出样例

输入#1
```
3 3
1 3 1
4 5 6
2 6 1
```
输出#1
```
6
```
输入#2
```
3 4
5 2 3 1
3 3 5 3
4 4 4 5
```
输出#2
```
4
```
输入#3
```
2 6
1 2 3 4 5 6
8 6 7 8 9 1
```
输出#3
```
8
```

首页