• Log InLog In
  • Register
Liquid`
Team Liquid Liquipedia
EST 10:54
CET 16:54
KST 00:54
  • Home
  • Forum
  • Calendar
  • Streams
  • Liquipedia
  • Features
  • Store
  • EPT
  • TL+
  • StarCraft 2
  • Brood War
  • Smash
  • Heroes
  • Counter-Strike
  • Overwatch
  • Liquibet
  • Fantasy StarCraft
  • TLPD
  • StarCraft 2
  • Brood War
  • Blogs
Forum Sidebar
Events/Features
News
Featured News
SC2 All-Star Invitational: Tournament Preview5RSL Revival - 2025 Season Finals Preview8RSL Season 3 - Playoffs Preview0RSL Season 3 - RO16 Groups C & D Preview0RSL Season 3 - RO16 Groups A & B Preview2
Community News
BSL Season 2025 - Full Overview and Conclusion6Weekly Cups (Jan 5-11): Clem wins big offline, Trigger upsets4$21,000 Rongyi Cup Season 3 announced (Jan 22-Feb 7)16Weekly Cups (Dec 29-Jan 4): Protoss rolls, 2v2 returns7[BSL21] Non-Korean Championship - Starts Jan 105
StarCraft 2
General
When will we find out if there are more tournament I am looking for StarCraft 2 Beta Patch files Stellar Fest "01" Jersey Charity Auction SC2 All-Star Invitational: Tournament Preview Weekly Cups (Jan 5-11): Clem wins big offline, Trigger upsets
Tourneys
SC2 All-Star Invitational: Jan 17-18 Sparkling Tuna Cup - Weekly Open Tournament SC2 AI Tournament 2026 $21,000 Rongyi Cup Season 3 announced (Jan 22-Feb 7) OSC Season 13 World Championship
Strategy
Simple Questions Simple Answers
Custom Maps
Map Editor closed ?
External Content
Mutation # 509 Doomsday Report Mutation # 508 Violent Night Mutation # 507 Well Trained Mutation # 506 Warp Zone
Brood War
General
[ASL21] Potential Map Candidates Video Footage from 2005: The Birth of G2 in Spain BW General Discussion BGH Auto Balance -> http://bghmmr.eu/ BSL Season 2025 - Full Overview and Conclusion
Tourneys
[Megathread] Daily Proleagues [BSL21] Non-Korean Championship - Starts Jan 10 Small VOD Thread 2.0 Azhi's Colosseum - Season 2
Strategy
Soma's 9 hatch build from ASL Game 2 Simple Questions, Simple Answers Game Theory for Starcraft Current Meta
Other Games
General Games
Nintendo Switch Thread Stormgate/Frost Giant Megathread Beyond All Reason Awesome Games Done Quick 2026! Mechabellum
Dota 2
Official 'what is Dota anymore' discussion
League of Legends
Heroes of the Storm
Simple Questions, Simple Answers Heroes of the Storm 2.0
Hearthstone
Deck construction bug Heroes of StarCraft mini-set
TL Mafia
Vanilla Mini Mafia Mafia Game Mode Feedback/Ideas
Community
General
US Politics Mega-thread Russo-Ukrainian War Thread NASA and the Private Sector Things Aren’t Peaceful in Palestine Canadian Politics Mega-thread
Fan Clubs
The herO Fan Club! The IdrA Fan Club
Media & Entertainment
Anime Discussion Thread [Manga] One Piece
Sports
2024 - 2026 Football Thread
World Cup 2022
Tech Support
Computer Build, Upgrade & Buying Resource Thread
TL Community
The Automated Ban List
Blogs
Navigating the Risks and Rew…
TrAiDoS
My 2025 Magic: The Gathering…
DARKING
Life Update and thoughts.
FuDDx
How do archons sleep?
8882
James Bond movies ranking - pa…
Topin
Customize Sidebar...

Website Feedback

Closed Threads



Active: 1153 users

C++ noob question

Blogs > eMbrace
Post a Reply
1 2 Next All
eMbrace
Profile Blog Joined January 2009
United States1300 Posts
Last Edited: 2009-10-17 02:49:29
October 17 2009 02:48 GMT
#1
I've been doing quite well in my class, but I've finally hit something that I can't figure out.

Basically, we have to decode a text file back to english (Caesar Cipher), and we have to run the text file through the our progame via the Command Prompt.

I've finished writing my code, but I can't get it to feed me back any output -- wrong or right.

I don't get an error or anything just this:

(checking to see if files I need are there, they are)
+ Show Spoiler +
[image loading]


(running the txt file through my program, maybe?)
+ Show Spoiler +
[image loading]


As you can see, nothing happens, and no errors appear either.

thats how I was instructed to do it and it's worked once before the other day, but now I finished writing my code and I can't test it =/

If you feel like taking the time, you can look at that as well:

+ Show Spoiler +
#include <iostream>
#include <iomanip>
#include <math.h>



using namespace std;


char reverseCaesar( char ch );
char convPunct( char ch );
char convDigit( char ch );
char convRest(char ch);
//***************************************************************************************************************************
int main()
{
char ch;
int change;


cin >> ch;

while ( cin )
{
char change;
if( isalpha(ch) )
{
change = reverseCaesar(ch);

}
else if (ispunct(ch) )
{
change = convPunct(ch);

}
else if (isdigit(ch) )
{
change = convDigit(ch);

}

else
change = convRest(ch);

cin >> ch;
}


system ("pause");
return 0;
}

//***************************************************************************************************************************

char reverseCaesar( char ch )
{
int i;

if (ch <= 47 && ch > 44)
{
i = (int)ch + 23;
}
else if (ch <=99 && ch > 96)
{
i = (int)ch +23;
}
else

i = (int)ch - 3;

return char(i);
}

char convPunct( char ch )
{
switch(ch)
{
case ',': return '0';
break;
case '.': return '1';
break;
case '$': return '2';
break;
case '&': return '3';
break;
case '%': return '4';
break;
case '*': return '5';
break;
case '(': return '6';
break;
case ')': return '7';
break;
case '?': return '8';
break;
case '!': return '9';

default: return ch;

}
}

char convDigit( char ch )
{
switch(ch)
{
case '0': return '!';
break;
case '1': return ',';
break;
case '2': return ')';
break;
case '3': return '(';
break;
case '4': return '?';
break;
case '5': return '-';
break;
case '6': return '&';
break;
case '7': return '$';
break;
case '8': return '.';
break;
case '9': return '+';
break;

default: return ch;

}
}

char convRest(char ch)
{
if(ch==21)
ch='\n';
else if(ch==22)
ch=' ';
else
ch=ch;

return ch;
}


I haven't added documentation, but it's fairly straight forward -- taking the characters from the txt file and decoding them (we had to write and use our own functions as well).

I'm willing to bet my program wouldn't work even if I could see it, but i'd at least like to try.

any help would appreciated, it's due in a couple of hours =)

if I have to i'll just submit and see if I can edit and resubmit tomorrow .

thanks.







*
Shade692003
Profile Joined August 2005
Canada702 Posts
October 17 2009 02:58 GMT
#2
been pretty long since I've done anything like coding or w/e, but if I understand correctly you enter your text file path as a parameter for your program? shouldn't there be parameters in your main then?
I hate the post below mine because it feels War3-ish.
DrTJEckleburg
Profile Blog Joined February 2009
United States1080 Posts
October 17 2009 02:58 GMT
#3
I have no help for your question, but I do believe that your reign at the top of LB will end after you bet on MBC over KT Rolster.
Im pretty good at whistling with my hands, especially when Im holding a whistle.
paper
Profile Blog Joined September 2004
13196 Posts
Last Edited: 2009-10-17 02:59:19
October 17 2009 02:59 GMT
#4
[image loading]


voting for MBC is your problem


edit: YOU GUYS ARE TOO FAST
Hates Fun🤔
keV.
Profile Blog Joined February 2009
United States3214 Posts
Last Edited: 2009-10-17 03:04:04
October 17 2009 03:00 GMT
#5
Wait a minute something isn't right here.


I'm pretty sure you can't read a txt file with cin, while expecting a char.

I don't know the details of your assignment, but do you take the file you are reading from as a parameter? If you do, then you definitely need to take some command line arguments. If not, then you can just open the file in your main or accept it by input string, and read char by char until the end of file.
"brevity is the soul of wit" - William Shakesman
AcrossFiveJulys
Profile Blog Joined September 2005
United States3612 Posts
Last Edited: 2009-10-17 03:05:10
October 17 2009 03:01 GMT
#6
I'm a little confused about what you're asking, but I think you are asking why your program doesn't "do" anything when you run it. Okay, so given that...

Your second screenshot shows you running the program with the file as input correctly.

Now, your program doesn't produce any output on the command prompt because you aren't telling it to print anything. Use cout if you want to print messages to the command prompt. If you are trying to create a new file that contains the translation of the original file, you'll need to use an ofstream and output to that, or use "> some_file" when running the program and print to some_file using cout.

eMbrace
Profile Blog Joined January 2009
United States1300 Posts
October 17 2009 03:01 GMT
#7
On October 17 2009 11:58 DrTJEckleburg wrote:
I have no help for your question, but I do believe that your reign at the top of LB will end after you bet on MBC over KT Rolster.


i'm on top for a reason
AcrossFiveJulys
Profile Blog Joined September 2005
United States3612 Posts
October 17 2009 03:03 GMT
#8
On October 17 2009 12:00 keV. wrote:
Wait a minute something isn't right here.


I'm pretty sure you can't read a txt file with cin, while expecting a char.


Yes you can. Since he's using the "<" operator when running the program, it changes the stdin stream (which is what cin uses) to refer to the file instead of user input.
Shade692003
Profile Joined August 2005
Canada702 Posts
October 17 2009 03:03 GMT
#9
On October 17 2009 12:00 keV. wrote:
Wait a minute something isn't right here.


I'm pretty sure you can't read a txt file with cin, while expecting a char.



I think the cin are for reading the characters in the text files, once they are read he changes them according to their values. could be wrong tho.

Anyhow there is no output like the other guy said
I hate the post below mine because it feels War3-ish.
eMbrace
Profile Blog Joined January 2009
United States1300 Posts
October 17 2009 03:05 GMT
#10
On October 17 2009 12:01 AcrossFiveJulys wrote:
I'm a little confused about what you're asking, but I think you are asking why your program doesn't "do" anything when you run it. Okay, so given that...

Your second screenshot shows you running the program with the file as input correctly.

Now, your program doesn't produce any output on the command prompt because you aren't telling it to print anything. Use cout if you want to print messages to the command prompt. If you are trying to create a new file that contains the translation of the original file, you'll need to use an ofstream and output to that.



to put it into a new file, they taught us this format

program < input.txt > new.txt

i get a new file with nothing in it =/
Shade692003
Profile Joined August 2005
Canada702 Posts
Last Edited: 2009-10-17 03:06:46
October 17 2009 03:05 GMT
#11
So hmm, shoudn't you cout that ''change'' variable?

Edit: Try to cout the change variable at the end of the while loop, might cout the value into the new text file.
I hate the post below mine because it feels War3-ish.
keV.
Profile Blog Joined February 2009
United States3214 Posts
Last Edited: 2009-10-17 03:06:53
October 17 2009 03:05 GMT
#12
On October 17 2009 12:03 AcrossFiveJulys wrote:
Show nested quote +
On October 17 2009 12:00 keV. wrote:
Wait a minute something isn't right here.


I'm pretty sure you can't read a txt file with cin, while expecting a char.


Yes you can. Since he's using the "<" operator when running the program, it changes the stdin stream (which is what cin uses) to refer to the file instead of user input.


I don't think reading from a file without a file handle is a good idea.

its sad how long its been since I've worked with simple I/O input...
"brevity is the soul of wit" - William Shakesman
vAltyR
Profile Blog Joined July 2008
United States581 Posts
Last Edited: 2009-10-17 03:08:40
October 17 2009 03:05 GMT
#13
Commenting is your best friend. Especially when you're asking others to help with your program. I didn't think it'd make that much difference, but I've had time where I look back on code and think "wtf was I doing here again?"

Do you need to separate it into functions like that? Sometimes it gets confusing debugging so many functions, especially when the code isn't your own.


EDIT: Wait a second... You're reading this from a file, right? You have nothing set up for file IO.
내 호버크라프트는 장어로 가득 차 있어요
Ironson
Profile Joined February 2008
20 Posts
October 17 2009 03:06 GMT
#14
The program is well formed, but it doesn't output anything! You need to write the output to "cout" and stream it into a file. Your command would become something like: pgm6 < input.txt > output.txt
keV.
Profile Blog Joined February 2009
United States3214 Posts
October 17 2009 03:07 GMT
#15
Like whats been said in this thread, you need to either rewrite the original file as you read char by char or you need to print the output to a a new file or screen.
"brevity is the soul of wit" - William Shakesman
eMbrace
Profile Blog Joined January 2009
United States1300 Posts
Last Edited: 2009-10-17 03:09:14
October 17 2009 03:08 GMT
#16
On October 17 2009 12:06 Ironson wrote:
The program is well formed, but it doesn't output anything! You need to write the output to "cout" and stream it into a file. Your command would become something like: pgm6 < input.txt > output.txt


ok right, but how exactly do I make my program cout all the decoded characters at once after the loop is over?

and sorry for the code with out comments -- we did have to write functions to use in the main, i guess it's a way of them making us learn how they work.



Ironson
Profile Joined February 2008
20 Posts
October 17 2009 03:09 GMT
#17
Before your second "cin >> ch;", place "cout << change;".
eMbrace
Profile Blog Joined January 2009
United States1300 Posts
Last Edited: 2009-10-17 03:14:24
October 17 2009 03:13 GMT
#18
On October 17 2009 12:09 Ironson wrote:
Before your second "cin >> ch;", place "cout << change;".



woah, it worked.

got all the decoded next in a new file.

thanks a lot everyone -- you may have saved my A in this class.

now I can watch MBC just roll over KT tonight
keV.
Profile Blog Joined February 2009
United States3214 Posts
October 17 2009 03:13 GMT
#19
this should give you simple error checking output.

+ Show Spoiler +

int main()
{
char ch;
int change;


cin >> ch;

while ( cin )
{
char change;
if( isalpha(ch) )
{
change = reverseCaesar(ch);


}
else if (ispunct(ch) )
{
change = convPunct(ch);


}
else if (isdigit(ch) )
{
change = convDigit(ch);


}

else
change = convRest(ch);
//output goes here

cin >> ch;
}


system ("pause");
return 0;
}

"brevity is the soul of wit" - William Shakesman
eMbrace
Profile Blog Joined January 2009
United States1300 Posts
October 17 2009 03:17 GMT
#20
On October 17 2009 12:13 keV. wrote:
this should give you simple error checking output.

+ Show Spoiler +

int main()
{
char ch;
int change;


cin >> ch;

while ( cin )
{
char change;
if( isalpha(ch) )
{
change = reverseCaesar(ch);


}
else if (ispunct(ch) )
{
change = convPunct(ch);


}
else if (isdigit(ch) )
{
change = convDigit(ch);


}

else
change = convRest(ch);
//output goes here

cin >> ch;
}


system ("pause");
return 0;
}



thanks a bunch kev
1 2 Next All
Please log in or register to reply.
Live Events Refresh
Wardi Open
12:00
#70
WardiTV1228
OGKoka 304
Rex111
Liquipedia
[ Submit Event ]
Live Streams
Refresh
StarCraft 2
Harstem 311
OGKoka 304
ProTech124
Rex 111
SC2Nice 21
RushiSC 15
Vindicta 8
StarCraft: Brood War
Calm 4301
GuemChi 1257
Larva 936
BeSt 808
Shuttle 659
Mini 633
Stork 624
EffOrt 564
ZerO 487
Snow 377
[ Show more ]
Rush 279
hero 174
firebathero 174
Barracks 98
Hyuk 76
JYJ 74
Sharp 72
Mind 70
Killer 57
Hm[arnc] 55
Aegong 39
Terrorterran 29
ToSsGirL 27
Sexy 23
Rock 20
GoRush 12
scan(afreeca) 12
SilentControl 11
ivOry 4
Dota 2
Gorgc5212
singsing2867
qojqva2441
Dendi537
syndereN311
420jenkins188
Counter-Strike
Fnx 716
fl0m437
adren_tv105
Super Smash Bros
Mew2King80
Other Games
hiko622
allub461
crisheroes393
Grubby388
Happy346
Fuzer 275
Hui .261
ArmadaUGS136
QueenE32
ZerO(Twitch)20
Organizations
Other Games
gamesdonequick2355
StarCraft: Brood War
Kim Chul Min (afreeca) 16
StarCraft 2
Blizzard YouTube
StarCraft: Brood War
BSLTrovo
sctven
[ Show 15 non-featured ]
StarCraft 2
• StrangeGG 57
• davetesta18
• AfreecaTV YouTube
• intothetv
• Kozan
• IndyKCrew
• LaughNgamezSOOP
• Laughngamez YouTube
• Migwel
• sooper7s
StarCraft: Brood War
• BSLYoutube
• STPLYoutube
• ZZZeroYoutube
League of Legends
• TFBlade1579
• Jankos1254
Upcoming Events
Monday Night Weeklies
1h 6m
OSC
19h 6m
PiGosaur Monday
1d 9h
The PondCast
1d 18h
OSC
1d 19h
Big Brain Bouts
4 days
Serral vs TBD
BSL 21
4 days
BSL 21
5 days
Wardi Open
6 days
Liquipedia Results

Completed

IPSL Winter 2025-26
SC2 All-Star Inv. 2025
NA Kuram Kup

Ongoing

C-Race Season 1
BSL 21 Non-Korean Championship
CSL 2025 WINTER (S19)
KCM Race Survival 2026 Season 1
OSC Championship Season 13
Underdog Cup #3
BLAST Bounty Winter Qual
eXTREMESLAND 2025
SL Budapest Major 2025
ESL Impact League Season 8
BLAST Rivals Fall 2025
IEM Chengdu 2025

Upcoming

Escore Tournament S1: W5
Acropolis #4
IPSL Spring 2026
Bellum Gens Elite Stara Zagora 2026
HSC XXVIII
Rongyi Cup S3
Nations Cup 2026
PGL Bucharest 2026
Stake Ranked Episode 1
BLAST Open Spring 2026
ESL Pro League Season 23
ESL Pro League Season 23
PGL Cluj-Napoca 2026
IEM Kraków 2026
BLAST Bounty Winter 2026
TLPD

1. ByuN
2. TY
3. Dark
4. Solar
5. Stats
6. Nerchio
7. sOs
8. soO
9. INnoVation
10. Elazer
1. Rain
2. Flash
3. EffOrt
4. Last
5. Bisu
6. Soulkey
7. Mini
8. Sharp
Sidebar Settings...

Advertising | Privacy Policy | Terms Of Use | Contact Us

Original banner artwork: Jim Warren
The contents of this webpage are copyright © 2026 TLnet. All Rights Reserved.