Styjun

What happens to unproductive professors?

Were Pandaria, Broken Isles, Northrend, Kul'Tiras and Zandalar also affected by the Cataclysm?

Party going through airport security at separate times?

Can I play a mimic PC?

Why does the US seem to have a rather low economic interest in Africa?

Is there a method for differentiating informative comments from commented out code?

How was the Shuttle loaded and unloaded from its carrier aircraft?

Found and corrected a mistake on someone's else paper -- praxis?

Write a function

Is it okay to use open source code to do an interview task?

Did the Ottoman empire suppress the printing press?

What are similar black and/or white permanents to Divine Visitation?

Is it okay to roll multiple attacks that all have advantage in one cluster?

When I press the space bar it deletes the letters in front of it

The origin of a particular self-reference paradox

Stacked light circle effect in Photoshop?

Misrepresented my work history

What is the parallel of Day of the Dead with Stranger things?

What do three diagonal dots above a letter mean in the "Misal rico de Cisneros" (Spain, 1518)?

Why different specifications for telescopes and binoculars?

What would +1/+2/+3 items be called in game?

Having decision making power over someone's assets

Automatically add points geometry while GPS logging?

Why is a mixture of two normally distributed variables only bimodal if their means differ by at least two times the common standard deviation?

Need help fixing a function for finding max_min_numbers in a text-file

Find and restore a deleted file in a Git repositoryHow do I save a String to a text file using Java?How to append text to an existing file in JavaFind all files in a directory with extension .txt in PythonReading a plain text file in JavaPython Print String To Text FileHow to read a large text file line by line using Java?C - fscanf raises EOF before end-of-fileReading numbers from a text file to an array in user defined function in CC Segmentation fault with fscanf

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;

0

I want to create a function with which I can find the lowest and highest number in a txt file. The problem is I don't know how to do it when there are letters and symbols involved. I also don't understand how to read a number, when it is glued to a letter or symbol.

I am basically stuck I created the function to read only from a text file full with numbers and now I want to make it to read the same numbers while ignoring letters.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 fscanf(fp_in, "%d", &N); //reads from stream
 min = max = N; 
 if (min > ch) min = ch; //checks values 
 if (max < ch) max = ch; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", min); //prints
 

Data read: a55 5 12 3 3a;

Expected output: 55, 3; Actual output: 51,3;

c file-io

share|improve this question

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Don't forget that after you've determined ch is a digit, you have already removed that character from the input stream. And so the call to fscanf will only read from the character that follows it. Use ungetc to put the character back into the stream. And before you update your min/max values, you should first test that the return value from fscanf is equal to 1, otherwise you cannot rely on the value in N being valid. Finally, you must not set min = max = N inside the loop. Your test is also wrong: compare with N, not ch.
  
  – paddy
  Mar 26 at 0:30
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  s/char ch;/int ch;/ [for a start]
  
  – wildplasser
  Mar 26 at 0:34
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Yet more errors: min is a pointer, so you must not just set it to some integer value. Instead, you probably want if (*min > N) *min = N;
  
  – paddy
  Mar 26 at 0:35
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Closing this question as "Too Broad" given the non-specific topic, and almost every line of code contains an error. This is unlikely to provide any value to future visitors of the site searching for answers to a specific question. The comments already provide valid feedback to help you, and you are welcome to post a new question if you are still having difficulty after implementing these suggestions.
  
  – paddy
  Mar 26 at 1:36
  

  
  
  
  

add a comment | 

0

I want to create a function with which I can find the lowest and highest number in a txt file. The problem is I don't know how to do it when there are letters and symbols involved. I also don't understand how to read a number, when it is glued to a letter or symbol.

I am basically stuck I created the function to read only from a text file full with numbers and now I want to make it to read the same numbers while ignoring letters.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 fscanf(fp_in, "%d", &N); //reads from stream
 min = max = N; 
 if (min > ch) min = ch; //checks values 
 if (max < ch) max = ch; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", min); //prints
 

Data read: a55 5 12 3 3a;

Expected output: 55, 3; Actual output: 51,3;

c file-io

share|improve this question

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Don't forget that after you've determined ch is a digit, you have already removed that character from the input stream. And so the call to fscanf will only read from the character that follows it. Use ungetc to put the character back into the stream. And before you update your min/max values, you should first test that the return value from fscanf is equal to 1, otherwise you cannot rely on the value in N being valid. Finally, you must not set min = max = N inside the loop. Your test is also wrong: compare with N, not ch.
  
  – paddy
  Mar 26 at 0:30
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  s/char ch;/int ch;/ [for a start]
  
  – wildplasser
  Mar 26 at 0:34
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  Yet more errors: min is a pointer, so you must not just set it to some integer value. Instead, you probably want if (*min > N) *min = N;
  
  – paddy
  Mar 26 at 0:35
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Closing this question as "Too Broad" given the non-specific topic, and almost every line of code contains an error. This is unlikely to provide any value to future visitors of the site searching for answers to a specific question. The comments already provide valid feedback to help you, and you are welcome to post a new question if you are still having difficulty after implementing these suggestions.
  
  – paddy
  Mar 26 at 1:36
  

  
  
  
  

add a comment | 

I want to create a function with which I can find the lowest and highest number in a txt file. The problem is I don't know how to do it when there are letters and symbols involved. I also don't understand how to read a number, when it is glued to a letter or symbol.

I am basically stuck I created the function to read only from a text file full with numbers and now I want to make it to read the same numbers while ignoring letters.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 fscanf(fp_in, "%d", &N); //reads from stream
 min = max = N; 
 if (min > ch) min = ch; //checks values 
 if (max < ch) max = ch; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", min); //prints
 

Data read: a55 5 12 3 3a;

Expected output: 55, 3; Actual output: 51,3;

c file-io

share|improve this question

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 fscanf(fp_in, "%d", &N); //reads from stream
 min = max = N; 
 if (min > ch) min = ch; //checks values 
 if (max < ch) max = ch; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", min); //prints
 

Expected output: 55, 3; Actual output: 51,3;

share|improve this question

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

share|improve this question

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

asked Mar 26 at 0:18

PeterPeter

1355 bronze badges

1 Answer
1

active

oldest

votes

0

Here, it prints maximum and minimum value and returns maximum value. It does not handle negative numbers. I would also suggest you to stay away from pointers if you are just starting to learn.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N = 0; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 N = N*10 + ch; //if previous digit is 2 and new digit is 3 N is set to 23
 
 else
 
 if (*min > N) *min = N; //checks values 
 if (max < N) max = N;
 N = 0; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", *min); //prints
 return max;
 

share|improve this answer

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

add a comment | 

Your Answer

StackExchange.ifUsing("editor", function ()
StackExchange.using("externalEditor", function ()
StackExchange.using("snippets", function ()
StackExchange.snippets.init();
);
);
, "code-snippets");

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "1"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55348173%2fneed-help-fixing-a-function-for-finding-max-min-numbers-in-a-text-file%23new-answer', 'question_page');

);

Post as a guest

Name

Email

Required, but never shown

0

Here, it prints maximum and minimum value and returns maximum value. It does not handle negative numbers. I would also suggest you to stay away from pointers if you are just starting to learn.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N = 0; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 N = N*10 + ch; //if previous digit is 2 and new digit is 3 N is set to 23
 
 else
 
 if (*min > N) *min = N; //checks values 
 if (max < N) max = N;
 N = 0; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", *min); //prints
 return max;
 

share|improve this answer

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

add a comment | 

0

Here, it prints maximum and minimum value and returns maximum value. It does not handle negative numbers. I would also suggest you to stay away from pointers if you are just starting to learn.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N = 0; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 N = N*10 + ch; //if previous digit is 2 and new digit is 3 N is set to 23
 
 else
 
 if (*min > N) *min = N; //checks values 
 if (max < N) max = N;
 N = 0; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", *min); //prints
 return max;
 

share|improve this answer

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

add a comment | 

Here, it prints maximum and minimum value and returns maximum value. It does not handle negative numbers. I would also suggest you to stay away from pointers if you are just starting to learn.

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N = 0; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 N = N*10 + ch; //if previous digit is 2 and new digit is 3 N is set to 23
 
 else
 
 if (*min > N) *min = N; //checks values 
 if (max < N) max = N;
 N = 0; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", *min); //prints
 return max;
 

share|improve this answer

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

int max_min_numbers(FILE *fp_in, int *min) 
 
 rewind(fp_in); // Because it is a part of a sub-menu
 char ch; 
 int max = 0, N = 0; 
 while ((ch = fgetc(fp_in)) != EOF) // reading until the file is over 
 
 if (isdigit(ch)) // if it is a number -->
 
 N = N*10 + ch; //if previous digit is 2 and new digit is 3 N is set to 23
 
 else
 
 if (*min > N) *min = N; //checks values 
 if (max < N) max = N;
 N = 0; 
 
 
 printf("Biggest number is: %dn", max); 
 printf("Lowest number is: %dn", *min); //prints
 return max;
 

share|improve this answer

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges

answered Mar 26 at 2:43

Suven PandeySuven Pandey

67122 silver badges1616 bronze badges