原

In the first case, the sequence $b$ could be obtained from the sequence $a = [1, 2, 3, 1, 2, 3]$ with the following partition: $[\color{red}{1}] + [\color{blue}{2, 3, 1}] + [\color{green}{2, 3}]$ . The sequence $b$ : $[\color{red}{1}, 1, \color{blue}{2, 3, 1}, 3, 2, \color{green}{2, 3}]$

改

In the first case, the sequence $b$ could be obtained from the sequence $a = [1, 2, 3, 1, 2, 3]$ with the following partition: $[\color{red}{1}] + [\color{blue}{2, 3, 1}] + [\color{green}{2, 3}]$ . The sequence $b$ : $[\color{red}{1}, 1, \color{blue}{2, 3, 1}, 3, \color{green}{2}, 2, 3]$