class App {
    public static void main(String[] args) {
    String str = "HexlEt";
    char ch = 'e';
    int result = countChars(str, ch);
    System.out.println("Chars quantity '" + ch + "' in a line '" + str + "': " + result);
}
 
    public static int countChars(String str, char ch) {
        // BEGIN
        var i = 0;
        var count = 0;
        var lowerChar = Character.toLowerCase(ch);
        while (i < str.length()) {
            var currentChar = Character.toLowerCase(str.charAt(i));
            if (currentChar == lowerChar) {
                count = count + 1;
            }
            i = i + 1;
        }
 
        return count;
        // END
    }
}

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