有没有办法用MapReduce生成排列？
输入文件:
1 title1 2 title2 3 title3
我的目标:
1,2 title1,title2 1,3 title1,title3 2,3 title2,title3
combinations hadoop mapreduce permutation
combinations ×1
hadoop ×1
mapreduce ×1
permutation ×1