cybersecurity · beginner · ~15 min
Validate the base64 alphabet.
Implement int is_base64_char(char c) returning 1 for A-Z, a-z, 0-9, '+', '/', and the padding '=', else 0.
int is_base64_char(char c) {
/* TODO */
return 0;
}
Solve this exercise in the browser editor — compile and run against the test harness, no setup required.