在if else语句上挣扎

Question

我对else和if语句很好奇。 为什么我的系统无法像这样工作。我无法找到更正它的方法，但是它不会运行并显示错误，否则就没有if。

导入java.util.Scanner;

公共类Q2Prac5Extra {

public static void main(String args[])
     {
     final float x=0.0254f;
     float height , weight;
     int age;
     String gender;


        System.out.print("************Ideal Weight Calculator************\n\nPlease enter your gender: ");
        gender = input.nextLine();

        System.out.print("Please enter your height: ");
        height = input.nextFloat();

        System.out.print("Please enter your age: ");
        age = input.nextInt();

        if(age<18)
        System.out.print("bye");
        else if (height<1.22);
        System.out.print("bye bye bye");

        else
            {

              if(gender.equals("male"))
                weight = 29.2f + 1.9f*((height-1.22f)/x);

             else
               weight = 28.6f + 1.7f*((height-1.22f)/x);

                System.out.print("\n\nThe ideal weight of this person is " + String.format("%.0f",weight) + "kg\n\n");  

            }

} }