a=b＋1(a，b是不为0的自然数)，那么a和b的最大公因数是____，最小公倍数____．

增加：在缺词处加一个漏字符号（∧），并在其下面写出该加的词。

删除：把多余的词用斜线（\）划掉。

修改：在错的词下划一横线，并在该词下面写出修改后的词。

注意：1).每处错误及其修改均仅限一词

2).只允许修改10处，多者（从第11处起）不计分。

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