public static void main(String[] args) {
    int degree = 100;
    int index = 1;　
    float Newdegree;
    Newdegree =(float) degree;//將度數強制轉型成float 
    if(index==1) { //當index = 1的情況 把攝氏度數轉華氏
        System.out.println("華氏度數為"+((Newdegree*9/5)+32)+"度");
    } 
    else if(index==2) {//當index = 2的情況 把華氏度數轉攝氏
        System.out.println("攝氏度數為"+((Newdegree-32)*5/9)+"度");
    }
}