<Codesignal> Is MAC48 Address?

Medium

A media access control address (MAC address) is a unique identifier assigned to network interfaces for communications on the physical network segment.

The standard (IEEE 802) format for printing MAC-48 addresses in human-friendly form is six groups of two hexadecimal digits (0 to 9 or A to F), separated by hyphens (e.g. 01-23-45-67-89-AB).

Your task is to check by given string inputString whether it corresponds to MAC-48 address or not.

Example

• For inputString = "00-1B-63-84-45-E6", the output should be
  isMAC48Address(inputString) = true;
• For inputString = "Z1-1B-63-84-45-E6", the output should be
  isMAC48Address(inputString) = false;
• For inputString = "not a MAC-48 address", the output should be
  isMAC48Address(inputString) = false.

Input/Output

• [execution time limit] 0.5 seconds (c)

• [input] string inputString

  Guaranteed constraints:
  15 ≤ inputString.length ≤ 20.

• [output] boolean

  • true if inputString corresponds to MAC-48 address naming rules, false otherwise.

[C] Syntax Tips

// Prints help message to the console
// Returns a string
char * helloWorld(char * name) {
    char * answer = malloc(strlen(name) + 8);
    printf("This prints to the console when you Run Tests");
    strcpy(answer, "Hello, ");
    strcat(answer, name);
    return answer;
}

---

Solution

bool isMAC48Address(char *inputString)
{
	if(strlen(inputString)!=17)
		return false;

	for(int i=0;i<strlen(inputString);i++)
		if(!(i%3==2?inputString[i]=='-':isdigit(inputString[i])||'A'<=inputString[i]&&'F'>=inputString[i]))
			return false;

	return true;
}