1. Just take four different numbers A2, four numbers from large to small alignment A23, four numbers from small to large rejuvenation A34, the maximum number of buckles get a 4 (ie, A2-A3) 5, The resulting A4 has been repeating the second step to fourth steps, and the operations have been used to get the same number. Please calculate this number? As 2341, A2 = 4321, A3 = 1234, A4 = 3087. A further thing for 3087
As long as the four numbers are not all, the last result is 6174
