练习五

今天早早起来用了10分钟敲了一个  小程序，一天一练把。坚持！

//题目：输入某年某月，判断是第几天。

#include<stdio.h>int year=0,month=0,day=0;int num=0;int decide(){printf("请输入要计算的年月日：\n");scanf("%d %d,%d",&year,&month,&day);if(year<0||month<0||month>12||day>31||day<0){printf("对不起：您输入不符合常理，请重新输入，年月日：\n");scanf("%d %d %d",&year,&month,&day);}switch(month){case 1: num=day; break;case 2: num=31+day; break;case 3: num=59+day; break;case 4: num=90+day; break;case 5: num=120+day; break;case 6: num=151+day; break;case 7: num=181+day; break;case 8: num=212+day; break;case 9: num=243+day; break;case 10: num=273+day; break;case 11: num=304+day; break;case 12: num=334+day; break;}return num;}int main(){int n=0;decide();if((year/4==0&&year/100!=0)||year/400==0)n=1;if(n=1&&month>2)num=num+1;printf("num=%d",num);return 0;}