My final else sentence isn't working in program(Java) [duplicate]

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• If else statements not working- why? 6 answers

So I've been trying to do this school exercise, the code compiles and all, but it won't print the final else sentence if the characters won't pair (aka aren't same brackets such as "( and )" or "[ and ]".

Any advice?

public  class PairOrNot {
    public static void main(String[] args) {
        char first;
        char last;
        System.out.println("Hello blahblah");
        System.out.println("1st input");
        first = In.readChar();
        System.out.println("2nd input");
        last = In.readChar();
        if (first == '(')
            if (last == ')')
                System.out.println(
                        "Blahblah " + first + " and " + last + " blahblah.");
        if (first == '[')
            if (last == ']')
                System.out.println(
                        "Blahblah " + first + " and " + last + " blahblah.");
        if (alku == '{')
            if (loppu == '}')
                System.out.println(
                        "Blahblah " + first + " and " + last + " blahblah.");
        if (first == '<')
            if (last == '>')
                System.out.println(
                        "Blahblah " + first + " and " + last + " blahblah.");
            else {
                System.out.println("Characters " + first + " and " + last
                        + " aren't a pair.");
            }
    }
}