Count backdoor root accounts

Challenge

Hunt for hidden root:

int count_backdoor_root(const char *text);

Given the full newline-separated /etc/passwd, count lines whose UID is 0 but whose username is NOT root. Those are backdoor accounts.

Input format

The full passwd file as one string.

Output format

Count of non-root UID-0 accounts.

Constraints

Handle a missing final newline and blank/malformed lines gracefully.

Starter code

#include <stddef.h>
/* Count lines (\n-separated) whose UID field == 0 but whose username is NOT "root". */
int count_backdoor_root(const char *text){ (void)text; return 0; }

Common mistakes

Matching root as a prefix instead of the exact first field; mishandling the last line when there is no trailing newline.

Edge cases to handle

root itself never counts; rooter (UID 0) does; blank lines are skipped.

Background lessons

• Find backdoor root accounts