v0.40: Create exercises. Challenge the community.

strcmp

Your mission

Implement gm_strcmp, your own strcmp, which compares two null-terminated strings byte by byte and returns an integer reflecting their lexicographic relationship.

See it in action

gm_strcmp("hello", "hello")

Expected result

Your checklist

For your own tracking. Tests grade your code.

Scan both strings simultaneously from index 0 until a differing byte or a null terminator is found.
Return 0 when both strings are identical up to and including their null terminator.
Return a negative integer when the first differing byte in s1 is smaller than the corresponding byte in s2.
Return a positive integer when the first differing byte in s1 is larger than the corresponding byte in s2.
Do not call any library function.

More examples

gm_strcmp("merge conflict on line one", "merge conflict on line two")

Expected result

negative value

Constraints

Expected files

strcmp.c

Allowed functions

None. Write every helper yourself.

libc

Standard C library

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

strcmp

Writing text without overflowing

Your mission

Implement gm_strcmp, your own strcmp, which compares two null-terminated strings byte by byte and returns an integer reflecting their lexicographic relationship.

See it in action

gm_strcmp("hello", "hello")

Expected result

Your checklist

For your own tracking. Tests grade your code.

Scan both strings simultaneously from index 0 until a differing byte or a null terminator is found.
Return 0 when both strings are identical up to and including their null terminator.
Return a negative integer when the first differing byte in s1 is smaller than the corresponding byte in s2.
Return a positive integer when the first differing byte in s1 is larger than the corresponding byte in s2.
Do not call any library function.

More examples

gm_strcmp("merge conflict on line one", "merge conflict on line two")

Expected result

negative value

Constraints

Expected files

strcmp.c

Allowed functions

None. Write every helper yourself.

libc

Standard C library

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

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Both strings emptyWaiting

02Identical stringsWaiting

03First less: dev stringWaiting

04First greater alphabeticallyWaiting

05First is a prefix extensionWaiting

06Second is a prefix extensionWaiting

07Single equal characterWaiting

strcmp

Your mission

Implement gm_strcmp, your own strcmp, which compares two null-terminated strings byte by byte and returns an integer reflecting their lexicographic relationship.

See it in action

gm_strcmp("hello", "hello")

Expected result

Your checklist

For your own tracking. Tests grade your code.

Scan both strings simultaneously from index 0 until a differing byte or a null terminator is found.
Return 0 when both strings are identical up to and including their null terminator.
Return a negative integer when the first differing byte in s1 is smaller than the corresponding byte in s2.
Return a positive integer when the first differing byte in s1 is larger than the corresponding byte in s2.
Do not call any library function.

More examples

gm_strcmp("merge conflict on line one", "merge conflict on line two")

Expected result

negative value

Constraints

Expected files

strcmp.c

Allowed functions

None. Write every helper yourself.

libc

Standard C library

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

v0.40: Create exercises. Challenge the community.

Meet Studio →

strcmp

Writing text without overflowing

Your mission

Implement gm_strcmp, your own strcmp, which compares two null-terminated strings byte by byte and returns an integer reflecting their lexicographic relationship.

See it in action

gm_strcmp("hello", "hello")

Expected result

Your checklist

For your own tracking. Tests grade your code.

Scan both strings simultaneously from index 0 until a differing byte or a null terminator is found.
Return 0 when both strings are identical up to and including their null terminator.
Return a negative integer when the first differing byte in s1 is smaller than the corresponding byte in s2.
Return a positive integer when the first differing byte in s1 is larger than the corresponding byte in s2.
Do not call any library function.

More examples

gm_strcmp("merge conflict on line one", "merge conflict on line two")

Expected result

negative value

Constraints

Expected files

strcmp.c

Allowed functions

None. Write every helper yourself.

libc

Standard C library

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

Tests

Run the tests to grade your code

Build your code, then check each test here. Open a result to inspect its output.

Build

01Both strings emptyWaiting

02Identical stringsWaiting

03First less: dev stringWaiting

04First greater alphabeticallyWaiting

05First is a prefix extensionWaiting

06Second is a prefix extensionWaiting

07Single equal characterWaiting