Boss: The FizzBuzz Gauntlet

Prove your foundations. Complete every task.

Boss task 1·code

Print the classic FizzBuzz sequence for every integer from 1 through 20 (both inclusive), one value per line, in order.

Rules for each number n:

If n is divisible by both 3 and 5 → print exactly FizzBuzz
Else if n is divisible by 3 → print exactly Fizz
Else if n is divisible by 5 → print exactly Buzz
Otherwise → print n as a decimal number

Use fmt.Println so each entry ends with a newline. Do not print any header, prefix, or trailing blank line. Case matters: the labels are Fizz, Buzz, FizzBuzz — nothing else.

Plate · main.go

Test suite · stdout assertion

prints the full sequencepending

Hint

Loop 1..20 and branch on n%15, then n%3, then n%5, otherwise print the number.

Boss task 2·code

Implement factorial(n int) int with 0! = 1 and negative n returning 0. A hidden test suite exercises 0, 1, 6, and 10.

Plate · main.go

Test suite · go test

TestFactorialZeropending
TestFactorialSmallpending
TestFactorialLargepending
TestFactorialNegativepending

Hint

Handle negative input first, then iterate for i := 2; i <= n; i++ multiplying into a running product seeded at 1.

Boss task 3·code

Implement isPrime(n int) bool: primes are integers > 1 with no divisors other than 1 and themselves. A hidden test suite includes edge cases (0, 1, 2, negatives) and larger primes.

Plate · main.go

Test suite · go test

TestIsPrimeSmallpending
TestIsPrimeLargerpending

Hint

Reject n < 2 first. Then trial-divide from 2 up to √n — no need to test beyond that.