strchr

Strings: walking and searching16

Objective

Implement a function that scans a string for the first occurrence of a character and returns a pointer to it.

Steps

Walk through the string character by character, comparing each one against c (which arrives as an int but is matched as a char).
On the first match, return a pointer to that character inside the string.
If the character never appears, return NULL.
The terminating '\0' counts as part of the string: searching for '\0' must return a pointer to the terminator, not NULL.
Do not modify the input buffer.

examples

$ strchr("rebase main", 'm')

main

$ strchr("git status", 'z')

(null)

$ strchr("commit", '\0')

(no output)

Constraints

Expected files

strchr.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines NULL

libc

Standard C library

Implements the contract of a function from the standard C library.

Tests

Run the tests to grade your code

Build

01Character in the middle

02Character is the first character

03Returns the first of several matches

04Character is the last character

05Character absent

06Searching for the terminator

07Empty string, character absent

08Empty string, searching for the terminator

strchr

Objective

Implement a function that scans a string for the first occurrence of a character and returns a pointer to it.

Steps

Walk through the string character by character, comparing each one against c (which arrives as an int but is matched as a char).
On the first match, return a pointer to that character inside the string.
If the character never appears, return NULL.
The terminating '\0' counts as part of the string: searching for '\0' must return a pointer to the terminator, not NULL.
Do not modify the input buffer.

examples

$ strchr("rebase main", 'm')

main

$ strchr("git status", 'z')

(null)

$ strchr("commit", '\0')

(no output)

Constraints

Expected files

strchr.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines NULL

libc

Standard C library

Implements the contract of a function from the standard C library.

strchr

Strings: walking and searching16

Objective

Implement a function that scans a string for the first occurrence of a character and returns a pointer to it.

Steps

Walk through the string character by character, comparing each one against c (which arrives as an int but is matched as a char).
On the first match, return a pointer to that character inside the string.
If the character never appears, return NULL.
The terminating '\0' counts as part of the string: searching for '\0' must return a pointer to the terminator, not NULL.
Do not modify the input buffer.

examples

$ strchr("rebase main", 'm')

main

$ strchr("git status", 'z')

(null)

$ strchr("commit", '\0')

(no output)

Constraints

Expected files

strchr.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines NULL

libc

Standard C library

Implements the contract of a function from the standard C library.

Tests

Run the tests to grade your code

Build

01Character in the middle

02Character is the first character

03Returns the first of several matches

04Character is the last character

05Character absent

06Searching for the terminator

07Empty string, character absent

08Empty string, searching for the terminator