output_description: Print the number of digits of a \+ b for each data set.
input_description: There are several test cases. Each test case consists of two non-negative
  integers a and _b_ which are separeted by a space in a line. The input
  terminates with EOF.
attempt: [print(len(str(sum(map(int, input().split()))))) for _ in range(1)]
  
problem_description: Digit Number
  
  Write a program which computes the digit number of sum of two integers a and
  b.
samples: [{"input": "7\n    1 99\n    1000 999", "output": "3\n    4"}]