请各位帮忙解释一下这段源代码 希望能详细的解释 谢谢！！
请各位帮忙解释一下这段源代码 希望能详细的解释#include<stdio.h>
#include<stdlib.h>
char* month_str[]={"January","February","March","April","May","June","July","August","September","October","November","December"};
char* week[]={"Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"};
int IsLeapYear(int year) /*find out the year is leap year or not*/
{
if((year%4==0&&year%100!=0)||(year%400==0))
return 1;
else
return 0;
}
int month_day(int year,int month)
{
int mon_day[]={31,28,31,30,31,30,31,31,30,31,30,31};
if(IsLeapYear(year)&&month==2)
return 29;
else
return(mon_day[month-1]);
}
int DaySearch(int year,int month,int day) /*search what day this day is*/
{
int c=0;
float s;
int m;
for(m=1;m<month;m++)
c=c+month_day(year,m);
c=c+day;
s=year-1+(float)(year-1)/4+(float)(year-1)/100+(float)(year-1)/400-40+c;
return ((int)s%7);
}
int PrintAllYear(int year)/*print the all year*/
{
int temp;
int i,j;
printf("\n\n%d Calander\n",year);
for(i=1;i<=12;i++)
{
printf("\n\n%s(%d)\n",month_str[i-1],i);
printf("0 1 2 3 4 5 6 \n");
printf("S M T W T F S \n\n");
temp=DaySearch(year,i,1);
for(j=1;j<=month_day(year,i)+temp;j++)
{
if(j-temp<=0)
printf(" ");
else if(j-temp<10)
printf("%d ",j-temp);
else
printf("%d ",j-temp);
if(j%7==0)
printf("\n");
}
}
return 0;
}
int main()
{
int option,da;
char ch;
int year,month,day;
printf("\nWelcome to use the WanNianLi system\n");
while(1)
{
printf("\nPlease select the service you need:\n");
printf("\n1 Search what day the day is");
printf("\n2 Search whether the year is leap year or not");
printf("\n3 Print the calander of the whole year");
printf("\n4 Exit\n");
scanf("%d",&option);
switch(option)
{
case 1:
while(1)
{
printf("\nPlease input the year,month and day(XXXX,XX,XX):");
scanf("%d,%d,%d,%c",&year,&month,&day);
da=DaySearch(year,month,day);
printf("\n%d-%d-%d is %s,do you want to continue?(Y/N)",year,month,day,week[da]);
fflush(stdin);
scanf("%c",&ch);
if(ch=='N'||ch=='n')
break;
}
break;
case 2:
while(1)
{
printf("\nPlease input the year which needs searched?(XXXX)");
scanf("%d",&year);
if(IsLeapYear(year))
printf("\n%d is Leap year,do you want to continue?(Y/N)",year);
else
printf("\n%d is not Leap year,do you want to continue(Y/N)?",year);
fflush(stdin);
scanf("%c",&ch);
if(ch=='N'||ch=='n')
break;
}
break;
case 3:
while(1)
{
printf("\nPlease input the year which needs printed(XXXX)");
scanf("%d",&year);
PrintAllYear(year);
printf("\nDo you want to continue to print(Y/N)?");
fflush(stdin);
scanf("%c",&ch);
if(ch=='N'||ch=='n')
break;
}
break;
case 4:
fflush(stdin);
printf("Are you sure?(Y/N)");
scanf("%c",&ch);
if(ch=='Y'||ch=='y')
exit(0);
break;
default:
printf("\nError:Sorry,there is no this service now!\n");
break;
}
}
return 0;
}
