/*

从键盘输入一个日期，格式为 yyyy-M-d

要求计算该日期与 1949 年 10 月 1 日距离多少天

例如：

用户输入了：1949-10-2

程序输出：1

用户输入了：1949-11-1

程序输出：31

*/

package Question20_29;

import java.util.Scanner;

public class Question24MustRemember {

public static int dayOfYear[]={365,366};//平年365天,闰年366天

public static int dayOfMonth[][]={

46

{0,31,28,31,30,31,30,31,31,30,31,30,31},

{0,31,29,31,30,31,30,31,31,30,31,30,31}

};

public static int dayOfYearIndex(int year){ //根据是否是闰年来给出dayOfYear的数组的下标

if((year%4==0&&year%100!=0)||year%400==0){

return 1;

}

return 0;

}

public static int dayApartFromTheBrginOfYear(int year,int month,int day){//计算month月day日是year年的第

几天

int days=day;

for (int i = 1; i < month; i++) {

days+=dayOfMonth[dayOfYearIndex(year)][i];

}

return days;

}

public static int apartDays(String startDayString,String endDayString ) {

String s1[]=startDayString.split("-");

String s2[]=endDayString.split("-");

int days=0;

int flag;

int startYear=Integer.parseInt(s1[0]);

int endYear=Integer.parseInt(s2[0]);

int startMonth=Integer.parseInt(s1[1]);

int endMonth=Integer.parseInt(s2[1]);

int startDay=Integer.parseInt(s1[2]);

int endDay=Integer.parseInt(s2[2]);

for (int i = startYear; i < endYear; i++) {

days+=dayOfYear[dayOfYearIndex(i)];

}

days+=dayApartFromTheBrginOfYear(endYear,endMonth,endDay);

days-=dayApartFromTheBrginOfYear(startYear,startMonth,startDay);

return days;

}

public static void main(String[] args) {

Scanner scanner=new Scanner(System.in);

String startDayString="1949-10-01";

String endDayString=scanner.nextLine();

System.out.println(apartDays(startDayString, endDayString));

}

47

}

运行结果：

输入日期格式为:(1949-10-2)

输入第一个日期:1949-10-2

输入第二个日期:1949-11-2

1949-10-2 到 1949-11-2

距离 31 天