Check If a String Contains All Binary Codes of Size K code example

Example 1: how to check if a string is in alphabetical order in java

public static boolean checkAlphabetic(String input) {
    for (int i = 0; i != input.length(); ++i) {
        if (!Character.isLetter(input.charAt(i))) {
            return false;
        }
    }

    return true;
}

Example 2: how to check if a string contains only alphabets and space in java

class IsAlpha
{
    public static boolean isAlpha(String s) {
        if (s == null) {
            return false;
        }
 
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i);
            if (!(c >= 'A' && c <= 'Z') && !(c >= 'a' && c <= 'z')) {
                return false;
            }
        }
        return true;
    }
 
    public static void main(String[] args)
    {
        String s = "ABCD";
        System.out.println("IsAlpha: " + isAlpha(s));
    }
}

Example 3: how to check if a string contains only alphabets and space in java

class IsAlpha
{
    public static boolean isAlpha(String s) {
        return s != null && s.chars().allMatch(Character::isLetter);
    }
 
    public static void main(String[] args)
    {
        String s = "ABCD";
        System.out.println("IsAlpha: " + isAlpha(s));
    }
}

Example 4: how to check if an arraylist contains a value in java recursion

public static boolean contains(ArrayList<Integer> list, int value) {
        return contains(list, value, 0);
}

private static boolean contains(ArrayList<Integer> list, int value, int idx) {
        boolean hasInt = false;
        
        if (idx < list.size()) {
            if (list.get(idx) == value) {
                hasInt = true;
            } else {
                hasInt = contains(list, value, idx + 1);
            }
        }
        
        return hasInt;
}