I gone in a totally different way, with Python 3:

def timeConversion(s): return(datetime.datetime.strptime(s, "%I:%M:%S%p").time().strftime("%H:%M:%S"))

Go:

/* * Complete the 'timeConversion' function below. * * The function is expected to return a STRING. * The function accepts STRING s as parameter. */

func timeConversion(s string) string {

len := len(s)
suf := s[len-2:]
hour,_ := strconv.Atoi(s[:2])
min:= s[3:5]
sec := s[6:8]

if suf == "AM" && hour == 12{
        hour = 0
}else if suf == "AM" && hour == 1{
        hour = 1        
}else if suf == "PM" && hour != 12{
        hour +=12
}

return fmt.Sprintf("%02d:%v:%v",hour,min,sec)        

}

# Simple Java Solution | Easy to Understand

public static String timeConversion(String s) {
    // Write your code here
    int n=s.length();
    String val=s.substring(n-2);
    int v=Integer.parseInt(s.substring(0,2));
    if(v==12){
        if(val.equals("PM"))
            return s.substring(0,n-2);
        else
            return String.valueOf(v-12)+"0"+s.substring(2,n-2);
    }
    if(val.equals("PM")){
        return String.valueOf(v+12)+s.substring(2,n-2);
    }
    return s.substring(0,n-2);
    }

here's my 2 liner on python

time = str((int(s[0:2])+12)%24 if (not s[0:2] =="12" and s[8]=="P") or (s[0:2] == "12" and s[8]=="A") else s[0:2])+s[2:8]
return "0"+time if time[1]==":" else time

!/bin/python3

import math def timeConversion(s): # Write your code here am_pm=s[-2:] hour=int(s[0:2]) min_sec=s[2:-2] if am_pm=="AM": if hour==12: hour=0 else: if hour!=12: hour+=12 return "{:02d}{}".format(hour,min_sec)

if name == 'main': fptr = open(os.environ['OUTPUT_PATH'], 'w')

s = input()

result = timeConversion(s)

fptr.write(result + '\n')

fptr.close()