codeforces#P1383D. Rearrange

    ID: 31318 远端评测题 1000ms 256MiB 尝试: 4 已通过: 3 难度: 10 上传者: 标签>brute forceconstructive algorithmsgraphsgreedysortings*2800

Rearrange

Description

Koa the Koala has a matrix $A$ of $n$ rows and $m$ columns. Elements of this matrix are distinct integers from $1$ to $n \cdot m$ (each number from $1$ to $n \cdot m$ appears exactly once in the matrix).

For any matrix $M$ of $n$ rows and $m$ columns let's define the following:

  • The $i$-th row of $M$ is defined as $R_i(M) = [ M_{i1}, M_{i2}, \ldots, M_{im} ]$ for all $i$ ($1 \le i \le n$).
  • The $j$-th column of $M$ is defined as $C_j(M) = [ M_{1j}, M_{2j}, \ldots, M_{nj} ]$ for all $j$ ($1 \le j \le m$).

Koa defines $S(A) = (X, Y)$ as the spectrum of $A$, where $X$ is the set of the maximum values in rows of $A$ and $Y$ is the set of the maximum values in columns of $A$.

More formally:

  • $X = \{ \max(R_1(A)), \max(R_2(A)), \ldots, \max(R_n(A)) \}$
  • $Y = \{ \max(C_1(A)), \max(C_2(A)), \ldots, \max(C_m(A)) \}$

Koa asks you to find some matrix $A'$ of $n$ rows and $m$ columns, such that each number from $1$ to $n \cdot m$ appears exactly once in the matrix, and the following conditions hold:

  • $S(A') = S(A)$
  • $R_i(A')$ is bitonic for all $i$ ($1 \le i \le n$)
  • $C_j(A')$ is bitonic for all $j$ ($1 \le j \le m$)
An array $t$ ($t_1, t_2, \ldots, t_k$) is called bitonic if it first increases and then decreases.

More formally: $t$ is bitonic if there exists some position $p$ ($1 \le p \le k$) such that: $t_1 < t_2 < \ldots < t_p > t_{p+1} > \ldots > t_k$.

Help Koa to find such matrix or to determine that it doesn't exist.

The first line of the input contains two integers $n$ and $m$ ($1 \le n, m \le 250$)  — the number of rows and columns of $A$.

Each of the ollowing $n$ lines contains $m$ integers. The $j$-th integer in the $i$-th line denotes element $A_{ij}$ ($1 \le A_{ij} \le n \cdot m$) of matrix $A$. It is guaranteed that every number from $1$ to $n \cdot m$ appears exactly once among elements of the matrix.

If such matrix doesn't exist, print $-1$ on a single line.

Otherwise, the output must consist of $n$ lines, each one consisting of $m$ space separated integers  — a description of $A'$.

The $j$-th number in the $i$-th line represents the element $A'_{ij}$.

Every integer from $1$ to $n \cdot m$ should appear exactly once in $A'$, every row and column in $A'$ must be bitonic and $S(A) = S(A')$ must hold.

If there are many answers print any.

Input

The first line of the input contains two integers $n$ and $m$ ($1 \le n, m \le 250$)  — the number of rows and columns of $A$.

Each of the ollowing $n$ lines contains $m$ integers. The $j$-th integer in the $i$-th line denotes element $A_{ij}$ ($1 \le A_{ij} \le n \cdot m$) of matrix $A$. It is guaranteed that every number from $1$ to $n \cdot m$ appears exactly once among elements of the matrix.

Output

If such matrix doesn't exist, print $-1$ on a single line.

Otherwise, the output must consist of $n$ lines, each one consisting of $m$ space separated integers  — a description of $A'$.

The $j$-th number in the $i$-th line represents the element $A'_{ij}$.

Every integer from $1$ to $n \cdot m$ should appear exactly once in $A'$, every row and column in $A'$ must be bitonic and $S(A) = S(A')$ must hold.

If there are many answers print any.

Samples

3 3
3 5 6
1 7 9
4 8 2
9 5 1
7 8 2
3 6 4
2 2
4 1
3 2
4 1
3 2
3 4
12 10 8 6
3 4 5 7
2 11 9 1
12 8 6 1
10 11 9 2
3 4 5 7

Note

Let's analyze the first sample:

For matrix $A$ we have:

    • Rows:
      • $R_1(A) = [3, 5, 6]; \max(R_1(A)) = 6$
      • $R_2(A) = [1, 7, 9]; \max(R_2(A)) = 9$
      • $R_3(A) = [4, 8, 2]; \max(R_3(A)) = 8$

    • Columns:
      • $C_1(A) = [3, 1, 4]; \max(C_1(A)) = 4$
      • $C_2(A) = [5, 7, 8]; \max(C_2(A)) = 8$
      • $C_3(A) = [6, 9, 2]; \max(C_3(A)) = 9$

  • $X = \{ \max(R_1(A)), \max(R_2(A)), \max(R_3(A)) \} = \{ 6, 9, 8 \}$
  • $Y = \{ \max(C_1(A)), \max(C_2(A)), \max(C_3(A)) \} = \{ 4, 8, 9 \}$
  • So $S(A) = (X, Y) = (\{ 6, 9, 8 \}, \{ 4, 8, 9 \})$

For matrix $A'$ we have:

    • Rows:
      • $R_1(A') = [9, 5, 1]; \max(R_1(A')) = 9$
      • $R_2(A') = [7, 8, 2]; \max(R_2(A')) = 8$
      • $R_3(A') = [3, 6, 4]; \max(R_3(A')) = 6$

    • Columns:
      • $C_1(A') = [9, 7, 3]; \max(C_1(A')) = 9$
      • $C_2(A') = [5, 8, 6]; \max(C_2(A')) = 8$
      • $C_3(A') = [1, 2, 4]; \max(C_3(A')) = 4$

  • Note that each of this arrays are bitonic.
  • $X = \{ \max(R_1(A')), \max(R_2(A')), \max(R_3(A')) \} = \{ 9, 8, 6 \}$
  • $Y = \{ \max(C_1(A')), \max(C_2(A')), \max(C_3(A')) \} = \{ 9, 8, 4 \}$
  • So $S(A') = (X, Y) = (\{ 9, 8, 6 \}, \{ 9, 8, 4 \})$