Little walrus Fangy loves math very much. That's why when he is bored he plays with a number performing some operations.

Fangy takes some positive integer $*x*$ and wants to get a number one from it. While $*x*$ is not equal to $1$, Fangy repeats the following action: if $*x*$ is odd, then he adds $1$ to it, otherwise he divides $*x*$ by $2$. Fangy knows that for any positive integer number the process ends in finite time.

How many actions should Fangy perform to get a number one from number $*x*$?

Input

The first line contains a positive integer $*x*$ in a binary system. It is guaranteed that the first digit of $*x*$ is different from a zero and the number of its digits does not exceed $10^{6}$.

Output

Print the required number of actions.

Note

Let's consider the third sample. Number $101110$ is even, which means that we should divide it by $2$. After the dividing Fangy gets an odd number $10111$ and adds one to it. Number $11000$ can be divided by $2$ three times in a row and get number $11$. All that's left is to increase the number by one (we get $100$), and then divide it by $2$ two times in a row. As a result, we get $1$.