Problem of the Day
A new programming or logic puzzle every Mon-Fri

Happy Monday!

Today's problem involves turning a long number in to a short number. The goal is to sum each digit of the number recursively until you reach a single digit. Here are a few test cases to make it easier to understand.

123456 = 1+2+3+4+5+6 = 2+1 = 3

99 = 9+9 = 1+8 = 9

Comments:

• Sami Suteria - 9 years, 6 months ago

  Run with node with the argument being after the filename $: node app.js 123456

  var input = 999;
  
  if(process.argv[2]){
      input = process.argv[2];
  }
  
  console.log(minify(input));
  
  function minify (input)
  {
      var sum = 0;
      input.toString().split("").forEach(function (value){
          sum += parseInt(value);
      });
      if (sum > 9){
          return minify(sum);
      }
      return sum;
  }
  

  reply permalink

• Anonymous - 9 years, 6 months ago

  #python
  def minify(number):
      minifiedsum = 0
      while number > 0:
  
          minifiedsum = minifiedsum + number % 10
          number = number/10
  
      if minifiedsum > 9:
          return minify(minifiedsum)
      else:
          return minifiedsum
  

  reply permalink

• Anonymous - 9 years, 6 months ago

  def minify_sum(n):
      return minify_sum(sum(map(int, str(n)))) if n > 9 else n
  

  reply permalink