Carry Count

When adding multi-digit numbers, you add one column at a time starting from the rightmost digit and moving left. Whenever the sum of a single column is a two-digit number, you carry the 1 into the column immediately to its left. This is called a carry.

Given two integers, write a program that counts how many carries occur while adding them together.

The input consists of several test cases. Each test case is a single line containing two integers, where each integer is a non-negative integer with at most 10 digits. The last line of the input is 0 0, and this line must not be processed.

For each test case, print on its own line the number of carries that occur when the two numbers are added.