Codeforces Round 295 (Div. 2)
B
Two Buttons
Codeforces
1400
原题
← AC →
翻译中…

Vasya has found a strange device. On the front panel of a device there are: a red button, a blue button and a display showing some positive integer. After clicking the red button, device multiplies the displayed number by two. After clicking the blue button, device subtracts one from the number on the display. If at some point the number stops being positive, the device breaks down. The display can show arbitrarily large numbers. Initially, the display shows number $*n*$.

翻译中…

Bob wants to get number $*m*$ on the display. What minimum number of clicks he has to make in order to achieve this result?

翻译中…

Input

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The first and the only line of the input contains two distinct integers $*n*$ and $*m*$ ($1 ≤ *n*, *m* ≤ 10^{4}$), separated by a space .

翻译中…

Output

翻译中…

Print a single number — the minimum number of times one needs to push the button required to get the number $*m*$ out of number $*n*$.

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Note

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In the first example you need to push the blue button once, and then push the red button once.

翻译中…

In the second example, doubling the number is unnecessary, so we need to push the blue button nine times.

翻译中…

样例

Input #1
4 6
Output #1
2
InputCopy OutputCopy
Input #2
10 1
Output #2
9
InputCopy OutputCopy
题目信息
题号
520B
时间限制
2 s
内存限制
256 MB
标签
DFS 及类似
图论
贪心
模拟
数学
最短路

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