RLE

def RLE(s):
#@param s: str
#@return str
  new_str = ''
  k = 1
  jump = 1
  lung = len(s)

  for i in range(lung):
    if i+1<lung:
      if s[i+1] == ' ':
        jump+=1

      else:
        if s[i+1] == s[i+1-jump]:
          k+=1

        else:
          if k>2:
            new_str+=str(k)+s[i+1-jump]
            k = 1
          else:
            new_str+=k*s[i+1-jump]
            k = 1

        jump = 1

    else:
          if k>2:
            new_str+=str(k)+s[i+1-jump]
            k = 1
          else:
            new_str+=k*s[i+1-jump]
            k = 1


  return new_str