HackerRank Java Lambda Expressions problem solution

In this HackerRank Java Lambda Expressions problem solution, you need to Write the following methods that return a lambda expression performing a specified action:

1. PerformOperation isOdd(): The lambda expression must return true if a number is odd or false if it is even.
2. PerformOperation isPrime(): The lambda expression must return true if a number is prime or false if it is composite.
3. PerformOperation isPalindrome(): The lambda expression must return true if a number is a palindrome or false if it is not

 HackerRank Java Lambda Expressions problem solution

 Write your code here
public static performOperation checkEvenOdd() {
    return evenOdd;
}
public static performOperation checkPrime() {
    return prime;
}
public static performOperation checkPalindrome() {
    return palindrome;
}

public static performOperation evenOdd  = (num) -> {

    if(num % 2 == 0) 
        return 0; 
    else return 1;
    
};

public static performOperation palindrome  = (num) -> {
    
  if (num < 0)
        return 1;
    int div = 1;
    while (num / div >= 10) {
        div *= 10;
    }
    while (num != 0) {
        int l = num / div;
        int r = num % 10;
        if (l != r)
            return 1;
        num = (num % div) / 10;
        div /= 100;
    }
    return 0;
    
};

public static performOperation prime = (num) -> {
    
    for(int i=2;i<num;i++) {
        if(num%i==0)
            return 1;
    }
    return 0;
    
};

}