【循环】排列（permutition）

<p> <!--[if gte mso 9]>Normal07.8 磅02falsefalsefalseMicrosoftInternetExplorer4<![endif]--><span style="font-size:medium;"><span style="font-family:宋体;">用</span><span style="font-family:&quot;">1</span><span style="font-family:宋体;">，</span><span style="font-family:&quot;">2</span><span style="font-family:宋体;">，</span><span style="font-family:&quot;">3</span><span style="font-family:宋体;">……</span><span style="font-family:&quot;">9</span><span style="font-family:宋体;">组成</span><span style="font-family:&quot;">3</span><span style="font-family:宋体;">items三位数</span><span style="font-family:&quot;">abc,def</span><span style="font-family:宋体;">和</span><span style="font-family:&quot;">ghi</span><span style="font-family:宋体;">，</span><span style="font-family:宋体;">每items数字恰好使用一次</span><span style="font-family:宋体;">，</span><span style="font-family:宋体;">要求</span><span style="font-family:&quot;">abc:def:ghi = 1:2:3</span><span style="font-family:宋体;">。输出所有解。提示：不必太动脑筋。</span><!--[if gte mso 9]><![endif]--><!--[if gte mso 10]> <![endif]--></span> </p>

<p> <span style="font-size:medium;">无输入。</span> </p>

<p> <span style="font-size:medium;">每组解一行，按abc从小到大输出各组解。每行abc，def，ghi三items数，用空格隔开。</span> </p>