n style="font-size: 14pt">，下面</span><span style="font-size: 14pt">n</span><span style="font-size: 14pt">行，每行</span><span style="font-size: 14pt">m</span><span style="font-size: 14pt">个字符给出了一个矩阵</span><span style="font-size: 14pt">A</span><span style="font-size: 14pt">，</span><span style="font-size: 14pt">A</span><span style="font-size: 14pt">ij</span><span style="font-size: 14pt">=1</span><span style="font-size: 14pt">如果第</span><span style="font-size: 14pt">j</span>