Problem:
Sum of Numbers

Write a program which reads an integer and prints sum of its digits.

Input

The input consists of multiple datasets. For each dataset, an integer x is given in a line. The number of digits in x does not exceed 1000.

The input ends with a line including single zero. Your program should not process for this terminal symbol.

Output

For each dataset, print the sum of digits in x.

Sample Input

123
55
1000
0

Sample Output

6
10
1

Solution in Ruby (judge verdict: Wrong Answer)

while line = gets
  sum = 0
  if line.to_i == 0 then break end
  while (c = line.slice!(0).to_i) != 0
    sum += c
  end
  puts sum
end