传送门
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题目描述
Now given two integers x and y, you can reverse every consecutive three bits in arbitrary number’s binary form (any leading zero can be taken into account) using one coin. Reversing (1,2,3) means changing it into (3,2,1).
Could you please find a way that minimize number of coins so that x = y? If you can, just output the minimum coins you need to use.
输入
The first line of input file contains only one integer T (1≤T≤10000) indicating number of test cases.
Then there are T lines followed, with each line representing one test case.
For each case, there are two integers x, y (0≤x,y≤1018) described above.
输出
Please output T lines exactly.
For each line, output Case d: (d represents the order of the test case) first. Then output the answer in the same line. If there is no way for that, print -1 instead.
题意描述