題目：輸入某年某月某日，判斷這一天是這一年的第幾天？
程序分析：以3月5日為例，應該先把前兩個月的加起來，然後再加上5天即本年的第幾天，特殊情況，閏年且輸入月份大於3時需考慮多加一天。
import java.util.*;
publicclass test {
publicstaticvoid main (String[]args){
int day=0;
int month=0;
int year=0;
int sum=0;
int leap;
System.
out.print("請輸入年,月,日\n");
Scanner input =
new Scanner(System.
in);
year=input.nextInt();
month=input.nextInt();
day=input.nextInt();
switch(month) /*先計算某月以前月份的總天數*/
{
case 1:
sum=0;
break;
case 2:
sum=31;
break;
case 3:
sum=59;
break;
case 4:
sum=90;
break;
case 5:
sum=120;
break;
case 6:
sum=151;
break;
case 7:
sum=181;
break;
case 8:
sum=212;
break;
case 9:
sum=243;
break;
case 10:
sum=273;
break;
case 11:
sum=304;
break;
case 12:
sum=334;
break;
default:
System.
out.println("data error");
break;
}
sum=sum+day; /*再加上某天的天數*/
if(year%400==0||(year%4==0&&year%100!=0))/*判斷是不是閏年*/
leap=1;
else
leap=0;
if(leap==1 && month>2)/*如果是閏年且月份大於2,總天數應該加一天*/
sum++;
System.
out.println("It is the the day:"+sum);
}
}
*
