有0，1，2三个数，此后，每次取出较大的两个数，用这两个数的和替换原先三个数中的任意一个。求需要使用最少的操作次数得到一个数x。-0, 1, 2 or three, Since then, every time you remove the larger of the two, with two numbers and replace any one of the original three numbers. Requirements need to use the minimum operation frequency and to obtain a number X.