GuessBrithday

import java.util.Scanner;import java.util.*;import java.lang.*;public class GuessBrithday{ public static void main(String[] args){  String set1=          "1 ,3 ,5 ,7 \n" +          "9 ,11,13,15\n" +          "17,19,21,23\n" +          "25,27,29,31";  String set2=          "2 ,3 ,6 ,7 \n" +          "10,11,14,15\n" +          "18,19,22,23\n" +          "26,27,30,31";  String set3=          "4 ,5 ,6 ,7 \n" +          "12,13,14,15\n" +          "20,21,22,24\n" +          "28,29,30,31";  String set4=          "8 ,9 ,10,11\n" +          "12,13,14,15\n" +          "24,25,26,27\n" +          "28,29,30,31";  String set5=          "16,17,18,19\n" +          "20,21,22,23\n" +          "24,25,26,27\n" +          "28,29,30,31";  List<String> strs = new ArrayList<String>();  strs.add(set1);  strs.add(set2);  strs.add(set3);  strs.add(set4);  strs.add(set5);  String tempstr = "";  String tempstr1 = "";  int birthday = 0;    String str;  Scanner input = new Scanner(System.in);  String[] tempstrArr;  for(int i=0;i<5;i++){  str=strs.get(i);  System.out.println(str + "\n Is your birthday is set? \n" +  "Enter 0 for No and Enter 1 for Yes:");  int answer = input.nextInt();  if(answer == 1){// 截取前两个字符   tempstr = str.substring(0,2);//去掉空格   tempstrArr = tempstr.split(" ");//   System.out.println(tempstrArr.length);//将String数组转换成String   for(int a=0;a<tempstrArr.length;a++){   tempstr1 = "";   tempstr1 += (String)tempstrArr[a];//     System.out.println(tempstr1);}   int tempbirthday = Integer.parseInt(tempstr1);   birthday = tempbirthday + birthday;}                                 // if{}//   System.out.println(birthday);}                                 // for(for(int i=0;i<5;i++))   System.out.println("your brithday is" + birthday);}}

问题总结如下：
1.List 的用法
2.String 数组
3.String 与 int 的转换 ， String数组转换为String型
4.截取List 用get(); ， 截取String 型 用substring(); ， 截取 String[] 用split();