Question

public boolean isPrime(int num){
// return true if the number is prime, false otherwise

}
public boolean isOdd(int num){
// return true if the number is odd, false otherwise

}

public String reverseMyString(String input){
// using a loop, reverse a string
// i.e. input = "hello", reversed answer: "olleh"
// i.e. input = "bye", reversed answer: "eyb"

}

public int pow(int base, int power){
// using for loop, calculate base raised to power
// i.e. base = 2, power = 3 = 2^3 = 2*2*2 = 8
// i.e. base = 5, power = 4 = 5^4 = 5*5*5*5 = 625

}

Answer 1

public boolean isPrime(int num) {
    for (int i = 2; i < num; ++i) {
        if (num % i == 0) {
            return false;
        }
    }
    return num > 1;
}

public boolean isOdd(int num) {
    return num % 2 == 1;
}

public String reverseMyString(String input) {
    String reverse = "";
    for (int i = 0; i < input.length(); i++) {
        reverse = input.charAt(i) + reverse;
    }
    return reverse;
}

public int pow(int base, int power) {
    int p = 1;
    for (int i = 0; i < power; i++) {
        p *= base;
    }
    return p;
}

public class UtilMethods {

    public boolean isPrime(int num) {
        for (int i = 2; i < num; ++i) {
            if (num % i == 0) {
                return false;
            }
        }
        return num > 1;
    }

    public boolean isOdd(int num) {
        return num % 2 == 1;
    }

    public String reverseMyString(String input) {
        String reverse = "";
        for (int i = 0; i < input.length(); i++) {
            reverse = input.charAt(i) + reverse;
        }
        return reverse;
    }

    public int pow(int base, int power) {
        int p = 1;
        for (int i = 0; i < power; i++) {
            p *= base;
        }
        return p;
    }

    public static void main(String[] args) {
        System.out.println(new UtilMethods().isPrime(2));
        System.out.println(new UtilMethods().isPrime(3));
        System.out.println(new UtilMethods().isPrime(4));
        System.out.println();

        System.out.println(new UtilMethods().isOdd(5));
        System.out.println(new UtilMethods().isOdd(6));
        System.out.println();

        System.out.println(new UtilMethods().reverseMyString("hello"));
        System.out.println(new UtilMethods().reverseMyString("bye"));
        System.out.println();

        System.out.println(new UtilMethods().pow(2, 3));
        System.out.println(new UtilMethods().pow(5, 4));
    }
}