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Time Limit: 2 s Memory Limit: 1024 MB Total points: 100

#3756. 字典序

الإحصائيات

对于序列 $A = (a_1, a_2, \dots, a_m)$ 和 $B = (b_1, b_2, \dots, b_m)$,定义 $A$ 的字典序比 $B$ 小,记作 $A < B$ ,当且仅当存在 $1 \leq p \leq m$ 使得 $a_p < b_p$ 且对于所有的 $1 \leq i < p$ 都有 $a_i = b_i$. 进一步地,定义 $A \leq B$ 当且仅当 $A < B$ 或者 $A = B$.

Bobo 有一个 $n$ 行 $m$ 列的矩阵 $C$. 他想找字典序最小的 $1, 2, \dots, m$ 的排列 $\sigma_1, \sigma_2, \dots, \sigma_m$, 使得 $S_1 \leq S_2 \leq \dots \leq S_n$,其中 $S_i = (C_{i, \sigma_1}, C_{i, \sigma_2}, \dots, C_{i, \sigma_m})$.

输入格式

输入文件包含多组数据,请处理到文件结束。

每组数据的第一行包含两个整数 $n$ 和 $m$.

接下来 $n$ 行,其中第 $i$ 行包含 $m$ 个整数 $C_{i, 1}, C_{i, 2}, \dots, C_{i, m}$.

  • $1 \leq n, m \leq 2000$
  • $1 \leq C_{i, j} \leq 10^9$
  • $n \times m$ 的总和不超过 $10^7$

输出格式

对于每组数据,如果有解,输出 $m$ 个整数,表示字典序最小的 $\sigma_1, \sigma_2, \dots, \sigma_m$. 否则输出 -1.

样例输入

4 3
4 3 3
1 5 1
1 5 1
3 5 2
2 2
1 1
1 2
2 2
2 2
1 1

样例输出

2 1 3
1 2
-1

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