strcspn

Strings: walking and searching16

Objective

Implement strcspn, which scans a string from the beginning and returns the index of the first character that appears in a given reject set.

Steps

The function takes two null-terminated strings: s and reject.
Walk through s from index 0. For each character, check whether it appears anywhere in reject.
Return the index of the first such character. If no character in s is found in reject, return the length of s.
Do not call any library function to do the scanning for you.

examples

$ strcspn("grep found nothing", "xyz")

$ strcspn("branch", "aeiou")

$ strcspn("", "abc")

Constraints

Expected files

strcspn.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines size_t

libc

Standard C library

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

Tests

Run the tests to grade your code

Build

01Empty source string

02First vowel in s

03No reject character found

04All characters in reject set

05Reject set has no overlap

strcspn

Objective

Implement strcspn, which scans a string from the beginning and returns the index of the first character that appears in a given reject set.

Steps

The function takes two null-terminated strings: s and reject.
Walk through s from index 0. For each character, check whether it appears anywhere in reject.
Return the index of the first such character. If no character in s is found in reject, return the length of s.
Do not call any library function to do the scanning for you.

examples

$ strcspn("grep found nothing", "xyz")

$ strcspn("branch", "aeiou")

$ strcspn("", "abc")

Constraints

Expected files

strcspn.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines size_t

libc

Standard C library

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

strcspn

Strings: walking and searching16

Objective

Implement strcspn, which scans a string from the beginning and returns the index of the first character that appears in a given reject set.

Steps

The function takes two null-terminated strings: s and reject.
Walk through s from index 0. For each character, check whether it appears anywhere in reject.
Return the index of the first such character. If no character in s is found in reject, return the length of s.
Do not call any library function to do the scanning for you.

examples

$ strcspn("grep found nothing", "xyz")

$ strcspn("branch", "aeiou")

$ strcspn("", "abc")

Constraints

Expected files

strcspn.c

Allowed functions

None. Write every helper yourself.

Allowed headers

<stddef.h>defines size_t

libc

Standard C library

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

Tests

Run the tests to grade your code

Build

01Empty source string

02First vowel in s

03No reject character found

04All characters in reject set

05Reject set has no overlap