Open the Lock

题目链接：https://vjudge.net/contest/176287#problem/A
题意：Each time, you can add or minus 1 to any digit. When add 1 to ‘9’, the digit will change to be ‘1’ and when minus 1 to ‘1’, the digit will change to be ‘9’. You can also exchange the digit with its neighbor. Each action will take one step.
心得：看代码吧，看得别人的。