public void genTruthTable4And3 () {
        boolean a; boolean b;
        a = false;
        b = false;
        if (a==false && b==false) {
            System.out.println (a+"      |"+ b +"       |"+ (a&&b) );}
        a = false;
        b = true;
        if (a==false && b==true) {
            System.out.println (a+"      |"+ b +"       |"+ (a&&b) );}
        a = true;
        b = false;
        if (a==true && b==false) {
            System.out.println (a+"      |"+ b +"       |"+ (a&&b) );}
        a = true;
        b = true;
        if (a==true && b==true9 {
            System.out.println (a+"      |"+ b +"       |"+ (a&&b) );}
    }