Hacker Rank Time Conversion problem solution Easiest

public static String timeConversion(String s) {
    // Write your code here
    //String temp = s;
    int hour=Integer.valueOf(s.substring(0, 2));
    if(s.substring(s.length()-2, s.length()).equalsIgnoreCase("AM")){
        hour=hour%12;
    }else{
        hour=(hour%12)+12;
    }
     
     if(hour<10){
         return "0".concat(String.valueOf(hour).concat(s.substring(2, s.length()-2)));
     }else{
         return String.valueOf(hour).concat(s.substring(2, s.length()-2));
     }

def timeConversion(s):
    a = (s[0]+ s[1])
    new_s = s[:-2]
    if s[-2] == "A":
        if a == "12":
            new_s = "00" + (new_s[2:])
            return (new_s)
        return new_s
    else:
        if a == "12":
            return new_s
        a1 = int(a) + 12
        new_s = (str(a1) + (new_s[2:]))
        return (new_s)

char* timeConversion(char* s) {
    
    int i = 0;
    int hms[3] = {0};
    char apm[2] = {0};
    char *result = NULL;
    char *token = NULL;
    
    result = (char *)malloc(9);
    memset(result, 0, 9);

    strncpy(apm, &s[8], 2);
    memset(&s[8], 0, 2);  

    token = strtok(s, ":");
    while (token != NULL) {
        hms[i] = atoi(token);
        token = strtok(NULL, ":");
        i++;
    }
    
    if(!strncmp(apm, "PM", 2))
    {
        if(hms[0] != 12)
        {
            hms[0] += 12;
        }
    }
    else if(!strncmp(apm, "AM", 2))
    {
        if(hms[0] == 12)
            hms[0] = 0;
    }
    
    sprintf(result, "%02d:%02d:%02d", hms[0],hms[1],hms[2]);
    
    return result;
}

public static string timeConversion(string s)
    {
		
        DateTime dt=Convert.ToDateTime(s);
				
        return   dt.ToString("HH:mm:ss");
    
		}