#!/bin/bash

# subtimes t1 t2
# -> "t1-t2"

for i in {1..2}
do
  inp=$(echo "${@:i:1}" | sed "s/^ *//" | sed "s/ *#.*$//")
  p1=$(echo "$inp" | tr ":" "  " | awk '{print $1}')
  p2=$(echo "$inp" | tr ":" "  " | awk '{print $2}')
  p3=$(echo "$inp" | tr ":" "  " | awk '{print $3}')
  for j in {1..2}
  do
    if [ "$p3" == "" ]
    then
      p3=$p2
      p2=$p1
      p1="0"
    fi
  done
  p4=$(echo $p3 | tr "." " " | awk '{print $2}')
  while [ ${#p4} -lt 6 ]
  do
    p4=${p4}"0"
  done
  f[$i]=$(echo $p4 | sed "s/^0*//" | sed "s/^$/0/")
  s[$i]=$(echo $p3 | tr "." " " | awk '{print $1}' | sed "s/^0*//" | sed "s/^$/0/")
  m[$i]=$(echo $p2 | sed "s/^0*//" | sed "s/^$/0/")
  h[$i]=$(echo $p1 | sed "s/^0*//" | sed "s/^$/0/")
done

fd=$[${f[1]}+${f[2]}]
ut=0
while [ $fd -ge 1000000 ]
do
  ut=$[$ut+1]
  fd=$[$fd-1000000]
done
while [ ${#fd} -lt 6 ]
do
  fd="0"$fd
done
sd=$[${s[1]}+${s[2]}+$ut]
ut=0
while [ $sd -ge 60 ]
do
  ut=$[$ut+1]
  sd=$[$sd-60]
done
md=$[${m[1]}+${m[2]}+$ut]
ut=0
while [ $md -ge 60 ]
do
  ut=$[$ut+1]
  md=$[$md-60]
done
hd=$[${h[1]}+${h[2]}+$ut]

echo $hd":"$md":"$sd"."$fd