#! /usr/bin/env python

def sec2str(sec):
  sign = ""
  if sec < 0:
    sign = "-";
    sec = -sec;
  sec1 = int(sec)
  sec100 = round((sec - sec1) * 100)
  minu = sec1 // 60
  sec1 = sec1 % 60
  hour = minu // 60
  minu = minu % 60
  return "%s%u:%02u:%02u.%02u" % (sign, hour, minu, sec1, sec100)

def str2sec(str):
  total = 0
  section = 0
  sign = 1
  decimal = 1
  for c in str:
    if c == ":":
      total = (total + sign * section) * 60
      section = 0
      sign = 1
      decimal = 1
    elif c == "-":
      sign = -sign
    elif c == ".":
      decimal = 0.1
    elif c >= "0" and c <= "9":
      if decimal < 1:
        section = section + int(c) * decimal
        decimal = decimal * 0.1
      else:
        section = section * 10 + int(c)
  total = total + sign * section
  return total