The variable 'ss' is similar to 'mm' or 'hh'. If others are getting displayed, it should also work well. Please recheck code, there might be any minor mistake. Else, post your submission link (or code) here, someone would be able to help for sure after looking at the code.

try adding 0 before %2d , that is , do %0d in your printf statement.

@Andyuriarte

There is no problem with the code. The problem is because of the underlying architecture on which your compiler is running. I tried it on windows, it gives correct result but gives wrong answer on linux. See this http://ideone.com/EV58mh

Here 'time' is stored before 'hour'. Same is happenning in your case and you are not getting correct value for ss.

Yeah, you can definitely use gets(). I used scanf() because it made this particular problem a lot easier.

Though, it depends a lot on the requirement, in general, I would suggest you to never use gets(). It's use is highly discouraged due to no protection to buffer overflow.

You get strong formatting features with scanf(), but its difficult (although possible) to use it properly with string buffers and impossible to be used safely for arithmetic input. Also, there can be failed scan or trailing newline in case input isn't well formatted. Hence, use scanf() only if you are completely aware of its functionality and know what you are doing (not recommended for new coders).

Use fgets(). It lets you specify buffer size. Just remember to remove trailing newLine (this also ensures buffer overflow protection).

In short, use fgets(), avoid scanf() and never use gets().

For this particular problem, you can use fgets() and pass it to sscanf() for scanf() like behavior, in case, you want to avoid scanf().

It's for specified output format. %2d will output in 2 digits format and %02d will left pad the result with '0'.

   Format      Data      Result
    %d:%d      11,5      11:5
  %2d:%2d      11,5      11: 5
%02d:%02d      11,5      11:05

There are ways to make code even shorter but this is far less readable than the above one, without any reduction in complexity since constants dont count. This is really short problem but 'readability' is really important factor in designing large softwares and shouldnt be ignored like this.

unable to get your code...please if you could explain a bit how it is working.

CAN YOU PLEASE EXPLAIN THE BELOW CODE: char plus12 = n_hour >= 12; n_hour += time[8] == 'P' ? (plus12 ? 0 : 12) : (plus12 ? -12 : 0); printf("%02d:%.*s:%.*s", n_hour, 2, time + 3, 2, time + 6);

Allison, thanks for the suggestion. Actually I added second 'if' to enhance readability, obviously that can be omitted. You can find a huge debate over the internet upon whether to bracket a single statement or not, so I won't go into that. Perhaps non-bracketing style have come into picture because of people moving out of C/Java style and working with Python/Haskell. Whatever is the reason, everything has its pros and cons. Avoiding it does "no harm"/"good", until you know what you are doing, well, it applies to any piece of code.

I usually look for an alternate/better solution even after solving the problem. That's why I wanted it to be more readable for someone looking for a different approach. Don't get mad over me because I didn't follow some particular style of coding. By the way, even "strcmp" is not needed that way, just check if t12[0]=='P'. One doesn't code in "CodeGolf" and "Hackathon" alike. Here, I just gave an alternate approach with enhanced readability, if it helps someone, with belief that target audience is intelligent enough to shorten the code. I seriously had no intention to make it "inelegant". Though, thanks again for the suggestions, would surely help someone get better insight :)

are you sure that we need the "else if" statement here?

"Explicit is better than implicit." -- Zen of Python

By explicitly checking for "AM" as well, we know that t12 has those two possible values.

I agree putting braces around the body of the if statements are necessary to avoid mistakes.

Hi,

I had a small question about the code and you seem knowledgable on the matter! I tried this by myself before looking at the comments and did mine along the lines of:

hh = hh % 12;
if ( strcmp(t12,"PM") == 0 ){
    hh += 12;
}

But everyone here seems to be using if/elses to treat 12 as a special case. Is there any performance benefit to doing so?

Thanks :)

That's a nice ternary.

You are absolutely right Sumit. It doesn't check for the sanity of the input. Since, the problem statement mentions that we'll be provided with "time" in proper AM/PM format, hence, the input won't contain min>59 or sec>59.

In my opinion, the problem emphasizes more upon Input/Output format rather than processing of data. Its given in "Warmup" section, probably, to familiarize new-coders with various input/output requirements. Though, other sections of "Algorithms" domain do contain problems with rigorous processing requirements, which might interest you more.

t12 is string (of length 2). It should be t12. Following link might help you : http://stackoverflow.com/questions/5406935/reading-a-string-with-scanf

Ultimately, it's up to you how you want to solve it. I found "extracting integers and later printing them with colons" easier than working with strings. Hence, I used scanf+printf for extracting & printing the result.

I have corrected that. Thanks !

This is the expected output.

The input is 12:33:45PM

The first one

That's because in the above code, in.substring(0,2)=="12" and in.substring(0,2)!="12" always return "same result" irrespective of the content in "in". Operators '==' and '!=' work on object identity, which means, even if the two strings have the same value, they are still two different objects and hence would always be considered unequal.

This can be corrected in two different ways :

1) Use in.substring(0,2).intern() in place of in.substring(0,2).

2) Use .equals() in place of ==.

Moreover, replace out[0] = 0; out[1] = 0; by out[0] = '0'; out[1] = '0';, otherwise it will still give wrong result (char, not int).

In short, the final conditions should become :

if(inChar[8] == 'A' && in.substring(0,2).equals("12")) {
    out[0] = '0';
    out[1] = '0';
}
else if(inChar[8] =='P' && !in.substring(0,2).equals("12")) {
    String s = "" + (Integer.parseInt(in.substring(0,2)) + 12);
    char[] f = s.toCharArray();
    out[0] = f[0];
    out[1] = f[1];
}

Let me know if you still face any issue !

you can use : System.out.printf("%02d:%02d:%02d",hh,mm,ss); in java

import datetime time = raw_input() dtdate = datetime.datetime.strptime(time,'%I:%M:%S%p') print dtdate.hour,":",dtdate.minute,":",dtdate.second

this is what i wrote but it says wrong error can you help me out. fixed it, some minor problems import datetime time = input() dtdate = datetime.datetime.strptime(time, '%I:%M:%S%p') print(dtdate.strftime("%H:%M:%S"))

Could you explain this? I tried this code in my python 2.7, but it told me that there's no modules with this name.

Here's my solution

time = raw_input()

night = 0
if 'PM' in time:
    night = 12

time = time[:8].split(':')

if time[0] == '12':
    time[0] = 0

time[0] = str(int(time[0]) + night)

newtime = str()
for x in time:
    newtime += x + ':'

if len(newtime) < 9:
    newtime = '0' + newtime

print newtime[:8]

@SanshiNron Are we suppose to use this? is this for checking our logic skills with the language or for using the goodness of language?

changing your if-else statement to this saves you another line:

if (hour != 12) final_time = final_time,2,6);

In c#, whe can do it even shorter:

static void ConvertTime(string time)
{
DateTime dateTime = DateTime.ParseExact(time, "hh:mm:sstt", 
    System.Globalization.CultureInfo.InvariantCulture);

Console.WriteLine(dateTime.ToString("HH:mm:ss"));
}

The "% 24" isn't needed. I forgot to remove it before submitting.