break, continue, and Finding Primes

Fine-tuning Loop Behavior

break exits the loop immediately. continue skips to the next iteration.

// break: find first multiple of 7
for (int i = 1; i <= 100; i++) {
    if (i % 7 == 0) {
        cout << "First: " << i;
        break;   // stop the loop
    }
}

// continue: print only odd numbers
for (int i = 1; i <= 10; i++) {
    if (i % 2 == 0) continue;  // skip evens
    cout << i << " ";  // 1 3 5 7 9
}

Efficient prime check

Only check divisors up to √n — if no divisor found by then, n is prime:

bool isPrime(int n) {
    if (n < 2) return false;
    for (int i = 2; i * i <= n; i++) {
        if (n % i == 0) return false;
    }
    return true;
}

Your Task

Implement isPrime(int n) as described above.