如何只使用switch...case来实现一个简单的数值范围划分

[csofwood]

输入年龄，然后判断出这个人是少年、青年、还是老年

直接在main方法里实现，不能用if、for等，只能用switch...case。输入一个年龄int age，如果在0~17之间，则打印出少年；18~29打印青年；30~59中年；60~100老年

最好是大家自己的思路

[csofwood]

晕，没人回答，是太简单了吗？

[huntor]

public void testAge(int age){
    switch(age){
        case   0: System.out.println("  0岁是少年！");break;
        case   1: System.out.println("  1岁是少年！");break;
        case   2: System.out.println("  2岁是少年！");break;
        case   3: System.out.println("  3岁是少年！");break;
        case   4: System.out.println("  4岁是少年！");break;
        case   5: System.out.println("  5岁是少年！");break;
        case   6: System.out.println("  6岁是少年！");break;
        case   7: System.out.println("  7岁是少年！");break;
        case   8: System.out.println("  8岁是少年！");break;
        case   9: System.out.println("  9岁是少年！");break;
        case  10: System.out.println(" 10岁是少年！");break;
        case  11: System.out.println(" 11岁是少年！");break;
        case  12: System.out.println(" 12岁是少年！");break;
        case  13: System.out.println(" 13岁是少年！");break;
        case  14: System.out.println(" 14岁是少年！");break;
        case  15: System.out.println(" 15岁是少年！");break;
        case  16: System.out.println(" 16岁是少年！");break;
        case  17: System.out.println(" 17岁是少年！");break;
        case  18: System.out.println(" 18岁是青年！");break;
        case  19: System.out.println(" 19岁是青年！");break;
        case  20: System.out.println(" 20岁是青年！");break;
        case  21: System.out.println(" 21岁是青年！");break;
        case  22: System.out.println(" 22岁是青年！");break;
        case  23: System.out.println(" 23岁是青年！");break;
        case  24: System.out.println(" 24岁是青年！");break;
        case  25: System.out.println(" 25岁是青年！");break;
        case  26: System.out.println(" 26岁是青年！");break;
        case  27: System.out.println(" 27岁是青年！");break;
        case  28: System.out.println(" 28岁是青年！");break;
        case  29: System.out.println(" 29岁是青年！");break;
        case  30: System.out.println(" 30岁是中年！");break;
        case  31: System.out.println(" 31岁是中年！");break;
        case  32: System.out.println(" 32岁是中年！");break;
        case  33: System.out.println(" 33岁是中年！");break;
        case  34: System.out.println(" 34岁是中年！");break;
        case  35: System.out.println(" 35岁是中年！");break;
        case  36: System.out.println(" 36岁是中年！");break;
        case  37: System.out.println(" 37岁是中年！");break;
        case  38: System.out.println(" 38岁是中年！");break;
        case  39: System.out.println(" 39岁是中年！");break;
        case  40: System.out.println(" 40岁是中年！");break;
        case  41: System.out.println(" 41岁是中年！");break;
        case  42: System.out.println(" 42岁是中年！");break;
        case  43: System.out.println(" 43岁是中年！");break;
        case  44: System.out.println(" 44岁是中年！");break;
        case  45: System.out.println(" 45岁是中年！");break;
        case  46: System.out.println(" 46岁是中年！");break;
        case  47: System.out.println(" 47岁是中年！");break;
        case  48: System.out.println(" 48岁是中年！");break;
        case  49: System.out.println(" 49岁是中年！");break;
        case  50: System.out.println(" 50岁是中年！");break;
        case  51: System.out.println(" 51岁是中年！");break;
        case  52: System.out.println(" 52岁是中年！");break;
        case  53: System.out.println(" 53岁是中年！");break;
        case  54: System.out.println(" 54岁是中年！");break;
        case  55: System.out.println(" 55岁是中年！");break;
        case  56: System.out.println(" 56岁是中年！");break;
        case  57: System.out.println(" 57岁是中年！");break;
        case  58: System.out.println(" 58岁是中年！");break;
        case  59: System.out.println(" 59岁是中年！");break;
        case  60: System.out.println(" 60岁是老年！");break;
        case  61: System.out.println(" 61岁是老年！");break;
        case  62: System.out.println(" 62岁是老年！");break;
        case  63: System.out.println(" 63岁是老年！");break;
        case  64: System.out.println(" 64岁是老年！");break;
        case  65: System.out.println(" 65岁是老年！");break;
        case  66: System.out.println(" 66岁是老年！");break;
        case  67: System.out.println(" 67岁是老年！");break;
        case  68: System.out.println(" 68岁是老年！");break;
        case  69: System.out.println(" 69岁是老年！");break;
        case  70: System.out.println(" 70岁是老年！");break;
        case  71: System.out.println(" 71岁是老年！");break;
        case  72: System.out.println(" 72岁是老年！");break;
        case  73: System.out.println(" 73岁是老年！");break;
        case  74: System.out.println(" 74岁是老年！");break;
        case  75: System.out.println(" 75岁是老年！");break;
        case  76: System.out.println(" 76岁是老年！");break;
        case  77: System.out.println(" 77岁是老年！");break;
        case  78: System.out.println(" 78岁是老年！");break;
        case  79: System.out.println(" 79岁是老年！");break;
        case  80: System.out.println(" 80岁是老年！");break;
        case  81: System.out.println(" 81岁是老年！");break;
        case  82: System.out.println(" 82岁是老年！");break;
        case  83: System.out.println(" 83岁是老年！");break;
        case  84: System.out.println(" 84岁是老年！");break;
        case  85: System.out.println(" 85岁是老年！");break;
        case  86: System.out.println(" 86岁是老年！");break;
        case  87: System.out.println(" 87岁是老年！");break;
        case  88: System.out.println(" 88岁是老年！");break;
        case  89: System.out.println(" 89岁是老年！");break;
        case  90: System.out.println(" 90岁是老年！");break;
        case  91: System.out.println(" 91岁是老年！");break;
        case  92: System.out.println(" 92岁是老年！");break;
        case  93: System.out.println(" 93岁是老年！");break;
        case  94: System.out.println(" 94岁是老年！");break;
        case  95: System.out.println(" 95岁是老年！");break;
        case  96: System.out.println(" 96岁是老年！");break;
        case  97: System.out.println(" 97岁是老年！");break;
        case  98: System.out.println(" 98岁是老年！");break;
        case  99: System.out.println(" 99岁是老年！");break;
        case 100: System.out.println("100岁是老年！");break;
        default: System.out.println("你确认你输入正确？！");break;
    }
}

以上代码非手工输入，由下面的clojure代码生成：
[code=Clojure](defn emitter [b e x]
(doseq [age (range b e)]
(println (format " case %3d: System.out.println(\"%3d岁是%s！\");break;" age age x))))
(println "public void testAge(int age){")
(println " switch(age){")
(emitter 0 18 "少年")
(emitter 18 30 "青年")
(emitter 30 60 "中年")
(emitter 60 101 "老年")
(println " default: System.out.println(\"你确认你输入正确？！\");break;")
(println " }")
(println "}")
[/code]

[evangelionxb]

import java.io.*;

public class tryCase1 {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		// TODO Auto-generated method stub
			
		int age;
		
		
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		try {
			age = Integer.parseInt(br.readLine());
					
			switch (age>0?(age>17?(age>29?(age>59?4:3):2):1):-1){
			case (1):
				System.out.println("少年");
				break;
			case (2):
				System.out.println("青年");
				break;
			case (3):
				System.out.println("中年");
				break;
			case (4):
				System.out.println("老年");
				break;
			case (-1):
				System.out.println("你输入的数值不合法");
				break;
				
			default:
				System.out.println("default");
				break;
			
			}
		} catch (NumberFormatException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

		
	}

}

用嵌套的三元表达
我的120岁也能判定

[csofwood]

[Quote=引用 3 楼 evangelionxb 的回复:]

Java code
import java.io.*;

public class tryCase1 {

/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub

……
[/Quote]
谢谢，我的跟你基本一样，下面是我第一次学编程时的思路，所以语法有点忘记了
switch (age>0?1:0)+(age>=18?1:0)+(age>=30?1:0)+(age>=60?1:0)+(age>100?1:0)
case (0): “精子”
case (1)：“少年”
case (2)：“青年”
case (3)：“中年”
case (4)：“老年”
case (5)：“妖怪”