Questions tagged [c]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0
votes
2answers
62 views

Is it possible to create/declare alphanumeric variable inside a for loop in c?

I want to create multiple variables like P0, P1, P2. The range will be given by the user. How to solve this in C?
0
votes
1answer
73 views

Pset4. Resize, less comfortable. Don't understand why code is working

I was having issues with my headers because I chose to create a separate header file for my new header changes. However, my code was not passing the check50. Upon researching and questioning, I found ...
0
votes
1answer
38 views

Segmentation fault on PSET3 recover

My program compiles, but wherever it runs I recieve a segmentation fault error. However i cannot see where the source of the problem is: #include <stdio.h> #include <stdlib.h> #include &...
0
votes
1answer
84 views

I have trouble enciphering in Vigenere Cipher CS50 pset2

I have issues incrementing the index of the key and wrapping the key to the beginning. I have tried what I know, I have watched the videos several times and I have been at this for 3 days. What am I ...
0
votes
1answer
38 views

Pset3 Tideman: Why is my sort_pairs function not working?

I'm green on all the criteria before sort_pair. Here's my code so far: // Sort pairs in decreasing order by strength of victory void sort_pairs(void) { // TODO // Create array of strengths of ...
0
votes
1answer
20 views

How does the CS50 IDE recognize C functions in advance?

I notice that functions like printf() and toupper() appear in blue without the relevant #include statements in files with names ending in .c. What is happening under the hood to make this happen?
0
votes
1answer
52 views

CS50 pset 1 water negative integers

Below is my code for the pset 1, im not sure why but whenever i put negatives for the "Minutes" i get a negative "Bottles" rather than an error. Help would be appreciated. #include <cs50.h> #...
0
votes
1answer
412 views

String being replaced by garbage before being printed

I have this code: #include <cs50.h> #include <stdio.h> #include <string.h> string increment_str(); int main() { string s = increment_str("xyz"); printf("String: %s\n", s); }...
0
votes
1answer
156 views

Pset5 Memory leak and errors in valgrind

I have been beating my head against a wall trying to solve my issues on my own, but I have gotten no where. I have two issues: 1) I have a small memory leak of 568 bytes in 1 block. My unload function ...
0
votes
1answer
72 views

Where is unistd being used in this CS50 example (is it superfluous)?

From what I see, the library is not used in this CS50 sample code and yet, it's included: #include <stdio.h> //#include <unistd.h> int main(int argc, char* argv[]) { if (argc != 2) ...
1
vote
1answer
15 views

Mario problem: Program got stuck at user input

// ** Below is the code of mario pset1, its taking input of width multiple times and not executing step after input// #include <cs50.h> #include <stdio.h> #include <math.h> int main(...
0
votes
1answer
111 views

Pset2: Vigenere Cipher, wrong output

In the following code there is no compiling error, but it does something wrong, as it gives me a wrong output. What it is supposed to do is: when the key is 'a' and the plaintext is 'a', output 'a', ...
0
votes
1answer
8 views

error : function definition not allowed here pls help

i got this error message pls help $ make triangle clang -ggdb3 -O0 -std=c11 -Wall -Werror -Wextra -Wno-sign-compare -Wno-unused-parameter -Wno-unused-variable -Wshadow triangle.c -lcrypt -lcs50 -...
0
votes
1answer
68 views

My do-while loop does not work

do { number = get_long_long("What is your credit card number? "); } while((number < 1000000000000) || (number >= 10000000000000000)); This loop is not accepting inputs. I do not ...
0
votes
1answer
104 views

pset2 How to get rid of spaces in the end of the milo banana_ _ _ _ (input)?

How to get rid of spaces in the end of the input? My code works perfectly with _ _ milla_ _ _ banana But I have issues with the case if _ _ _ milla_ _ banana_ _ _ when I have spaces in the end How ...
0
votes
0answers
22 views

Why do Escape Sequences in C work differently when I compile code by using GCC?

Why do Escape Sequences in C work differently when I compile code by using GCC? For example, Input: #include <stdio.h> int main(void){ printf("Hello world\n"); } Output in CS50 ...
0
votes
1answer
90 views

PSET 4 Filters CS50

void reflect(int height, int width, RGBTRIPLE image[height][width]) { RGBTRIPLE temp[height][width]; for (int i = 0 ; i < height ; i++) { for (int j = 0 ; j < width ; j++...
0
votes
1answer
72 views

pset2 vigenere. My code handles text inconsistently

I've got it working nearly perfectly. It works if the text is in lowercase, but I see that it's not working quite right when using uppercase. In check50 it only fails with lowercase: encrypts "BaRFoo"...
0
votes
1answer
13 views

pset2//caesar : strspn result

I'm struggling to understand : (argc != 2 || argv[1][strspn(argv[1], "1234567890")]) It works, but I'm trying to understand what's going on inside the if evaluation, and the value argv[1][...
0
votes
1answer
81 views

Recursive Binary Search Exit Code Errors

I wrote the following recursive binary search function. No matter which exit codes I use (e.g., true, false, 1, 0, -1, "Swedish Chef"), I fail at least two of the checks I need to pass. The code ...
0
votes
1answer
107 views

Game Of Fifteen Won Function

my won function for Game of Fifteen does not exit. check50 says it timed out waiting for the program to exit. My other functions for game of fifteen seem fine. Help would be appreciated! bool won(...
0
votes
1answer
63 views

Find hex values inside a string in C?

I have a long string "given_string", and I'm trying to find hex values within that string. Here's a simplified example: /* Find a sub-string in a given string: */ char * given_string = &...
0
votes
3answers
136 views

FIFTEEN works perfectly but doesn't pass Check50

My program works perfectly. Though, my Check50 says that my program only compiles and runs, nothing else. I think this has to do with my draw function, but I can't spot the mistake Can anyone help me ...
0
votes
1answer
116 views

Problem with my credit.c code

My credit.c code keeps inserting huge numbers in my array for seemingly no apparent reason. For example the user enters 45231 for the credit card number, the beginning of the array is fine and ...
1
vote
1answer
25 views

'stadio.h' file not found

#include <stadio.h> int main(void) { printf("hello, world"); } when i type make hello clang -ggdb3 -O0 -std=c11 -Wall -Werror -Wextra -Wno-sign-compare -Wno-unused-parameter -Wno-...
0
votes
2answers
583 views

While Loop in C only executing once and then stopping

I have created a function in C that tests if an integer in between a range of 100 (min) and 500 (max) - The function calls on another function called "getInt()" which tests whether the integer is ...
0
votes
1answer
190 views

incompatible pointer types passing 'string' (aka 'char *') to parameter of type 'string *' (aka 'char **')

Im writing a funtion that takes string as a argument and gives back a integer. This function counts lenght of a string entered at the command line argument. I get an error :" incompatible pointer ...
0
votes
1answer
350 views

Pset5 speller: how can I navigate through the Trie and free the nodes?

so I am stuck on this PSET5 speller for a quite while now, trying different approaches, looking at available information in CS50, shorts, pset problem explanation and I couldn't get to free all the ...
0
votes
2answers
124 views

How to submit a Pset without appliance?

I want to submit the source code for problem set 1 . But I don't have the cs50 appliance . So what should I do?
0
votes
2answers
140 views

Why isn't my block on pset1 turning into a staircase?

I am currently working on pset1 Mario, less comfortable. I am running my c to turn the hashtags into a staircase, but when I run the code, it is only a block. What is wrong with my code? Thank you all ...
0
votes
1answer
34 views

credit pset1 cs50 sum while loop

I was doing the credit problem with the visa test card in the page: 4003600000000014 It passed that test, however in other tests it doesn't pass. I think it's a matter of the sum that it can't compute ...
0
votes
3answers
178 views

pset1 mario. can't fix errors, please help!

I can't understand what's wrong with the code. I've changed it many times, but errors are always similar.Can anyone please check the code and tell what's wrong?
0
votes
1answer
3k views

difference between char ** and char *[] in C

what is the difference between char **str and char *str[] in C? int main(void){ char **str = (char **)malloc(5 * sizeof(char*)); char *str2[5]; str[1] = "hello"; str2[1] = "hello"; ...
0
votes
1answer
82 views

pset3 tideman cs502020 locked pairs error

I am new to coding and I am trying to solve the locked pairs part of the Tideman problem. Currently, I am receiving the following two errors: :) lock_pairs locks all pairs when no cycles :( lock_pairs ...
2
votes
1answer
1k views

C Preprocessor Output: What is <built-in>

I wrote one of the most simple programs I could imagine: int main (void) { int a; } As you can see, there are no include files. The purpose is to understand a little bit more about the ...
0
votes
1answer
17 views

Unable to confirm user input is a number using isdigit in c

My code is attempting to; take user input from the command line; check if the input is a whole number; confirm positively if so; confirm negatively if not; however all numbers return a negative ...
0
votes
1answer
15 views

Seg fault (storing file pointer as NULL initially maybe?)

// img file pointer FILE* img = NULL; char* file_name = NULL; int file_count = 0; int bytes_written = 512; // repeat until end of memory card while (bytes_written == 512) // ...
0
votes
1answer
97 views

I'm getting a Segmentation Fault when running recover.c

Seems like others also had the same problem of a Segmentation Fault when trying to do solve this, but I'm not going to look at those. I already liked at another person's code while I was stuck trying ...
0
votes
1answer
128 views

I am stuck on CS50 vigenere

Hi please see the link for the code I am working with. I think the layout is correct but cannot seem to find the correct algorithm to solve this problem. https://github.com/ionakathryn/cs50-pset2/...
2
votes
1answer
7k views

Pset3: Plurality - Weird output!

This program is for counting the plurality for a list of candidates, Check Description for more info, The program works like this: Enter the candidate's name as an argument when running the program ...
0
votes
1answer
237 views

pset4 increment pointer of type RGBTRIPLE by BYTE

In pset4, resizing an image, I decided to try out pointers and memory allocation to learn more about it, but I've run into an issue with my approach... I've created a pointer and allocated memory for ...
0
votes
2answers
889 views

Segmentation fault: cannot replace character in string

string increment(string s, int loc) { char c = s[loc]; c += 1; s[loc] = c; return s; } increment("A", 0); returns Segmentation fault at s[loc]=c;and I have no idea why. Is there a specific ...
0
votes
1answer
232 views

How do I load words in speller that are mixed letters and numbers?

I'm struggling with pset 6 (quite difficult logical and implementation wise, but I like this level of difficulty and this challenge). I'm implementing load and I just found out that I'm 34 words off ...
1
vote
2answers
1k views

passing argument 1 of ‘strlen’ from incompatible pointer type

How to make this working? How to properly find the length of these 8 listings? Whenever I execute it gives me following error. *passing argument 1 of ‘strlen’ from incompatible pointer type * #...
2
votes
5answers
2k views

How can I get the cs50.h to run in Visual Studio Code?

I downloaded both the cs50.c and cs50.h files from GitHub and put them in the folder where all the header files are. VSC even recognizes the #include <cs50.h> in the code but I get the error in ...
0
votes
1answer
18 views

PSet3 Tideman , error with updating ranks array

bool vote(int rank, string name, int ranks[]) { for (int i = 0; i < candidate_count; i++) { if (strcmp(name, candidates[i]) == 0) { ranks[rank] = name; ...
0
votes
1answer
1k views

Pset3: Tideman - sort_pairs error!

I have difficulty to understand what should the output of the function sort_pairs() should be!, What I understand is I should take the unsorted pairs[] and sort it. For example, this is pairs[] ...
0
votes
1answer
29 views

How to swap strings?

The main problem comes when we swap strings of unknown lengths. Lets say we have two strings assigned to two variables say a, b. Now if I use a temporary string say c, and use strcpy(c,a), then use ...
0
votes
1answer
17 views

function output?

I can't get this function to output the desired value of 0.07. #include <stdio.h> #include <cs50.h> #include <math.h> float i = 1.32; float quar_val = 0.25; int func(float val, ...
0
votes
1answer
62 views

pset1 credit: I am unable to identify what's wrong in the logic of my code?

Kindly tell me what mistake have I made in this program? pset1 Credit: (my code) https://pastebin.pl/view/5646dbf1

1
2 3 4 5
12