#P6939. Binary Number

    ID: 5796 远端评测题 1000ms 64MiB 尝试: 0 已通过: 0 难度: (无) 上传者: 标签>2021“MINIEYE杯”中国大学生算法设计超级联赛-热身赛(2021湘潭全国邀请赛-重现)

Binary Number

Problem Description

You are given two binary numbers $x$ and $y$ $(0 \leq y \leq x)$. $x$ is variable while $y$ is constant. You need to perform some steps of operations on $x$ and finally make $x$ equal to $y$.

In each step, you can perform one of the two operations below.


* Make $x$ become $x-1$. This operation can be performed only if $x>0$.
* If the $i$-th most significant bit of $x$ is 1, and the $i+1$-th most significant bit of $x$ is 0, we can swap the two bits in $x$. That is to say, for two adjacent bits, if the `left` is $1$ and the `right` is $0$, we can swap them (change $10$ to $01$).

Now you need to find the minimum steps we need to make $x$ become $y$.

Input

There are multiple test cases.

For each test case, there is a line containing two binary integers $x$ and $y$.

The total length of all binary integers in a test file is not larger than $2000000$.

Output

For each test case, output an integer in a line, denoting the minimum steps to make $x$ become $y$.

10100 1000 1000001 11111 10010 0 11111 101 101001 10010
4 3 7 11 4