nt day; int year; }; bool isLeap(struct date d);//判断是否为闰年 int numberOfDays(struct date d); int main(int argc, const char * argv[]) { struct date today, tomorrow; printf(Enter today's date(mm dd yyyy):); scanf(%i %i %i, &today.month, &today.day, &today.year); if(today.day != numberOfDays(today)){ tomorrow.day = today.day + 1; tomorrow.month = today.month; tomorrow.year = today.year; } else if (today.month == 12){ tomorrow.day = 1; tomorrow.month = 1; tomorrow.year = today.year + 1; } else{ tomorrow.day = 1; tomorrow.month = today.month + 1; tomorrow.year = today.year; } printf(Tomorrow's date is %i-%i-%i. , tomorrow.year, tomorrow.month, tomorrow.day); return 0; } int numberOfDays(struct date d){ int days; const int daysPerMonth[12] = {31,28,31,30,31,30,31,31,30,31,30,31}; if(d.month == 2 && isLeap(d)){ days = 29;//闰年 } else{ days = daysPerMonth[d.month - 1]; } return days; } bool isLeap(struct date d){ bool leap = false; if ( (d.year % 4 == 0 && d.year % 100 != 0) || d.year % 400 == 0){ leap = true; } return leap; }
输出：
Enter today's date(mm dd yyyy):12 31 2014
Tomorrow's date is 2015-1-1.
Program ended with exit code: 0
指向结构的指针
struct date {
int month;
int day;
int year;
} myday;
struct date *p = &myday;
(*p).month = 12;
p->month = 12;
* 用->表示指针所指向的结构变量中的成员
//
// main.c
// structure
//
// Created by liuxinming on 15/4/12.
// Copyright (c) 2015年 liuxinming. All rights reserved.
//
#include
struct point {
int x;
int y;
};
struct point* getStruct(struct point*);
void output(struct point);
void print(const struct point *p);
int main(int argc, const char * argv[]) {
struct point y = {0, 0};
getStruct(&y);
output(y);
output(*getStruct(&y));
print(getStruct(&y));
return 0;
}
struct point* getStruct(struct point *p){
scanf(%d, &p->x);
scanf(%d, &p->y);
printf(%d, %d
, p->x, p->y);
return p;
}
void output(struct point p){
printf(%d, %d
,p.x, p.y);
}
void print(const struct point *p){
printf(%d, %d,p->x, p->y);
}
输出：
10
50
10, 50
10, 50
结构数组
struct date dates[100];
struct date dates[] = {
{4,5,2005},
{2,4,2005}
};
案例：
//
// main.c
// structure
//
// Created by liuxinming on 15/4/12.
// Copyright (c) 2015年 liuxinming. All rights reserved.
//
#include
struct time{
int hour;
int minutes;
int seconds;
};
struct time timeUpdate(struct time now);
int main(void) {
struct time testTime[5] = {
{11,59,59},
{12,0,0},
{1,29,29},
{23,59,59},
{19,12,27}
};
int i;
for (i = 0; i < 5; i++) {
printf(Time is %.2i:%.2i:%.2i
, testTime[i].hour,testTime[i].minutes, testTime[i].seconds);
testTime[i] = timeUpdate(testTime[i]);
printf(... one second later it's %.2i:%.2i:%.2i
, testTime[i].hour,testTime[i].minutes, testTime[i].seconds);
}
return 0;
}
struct time timeUpdate(struct time now){
++ now.seconds;
if( now.seconds == 60){
now.seconds = 0;
++ now.minutes;
if (now.minutes == 60){
now.minutes = 0;
++ now.hour;
if(now.hour == 24){
now.hour = 0;
}
}
}
return now;
}
输出：
Time is 11:59:59
... one second later it's 12:00:00
Time is 12:00:00
... one second later it's 12:00:01
Time is 01:29:29
... one second later it's 01:29:30
Time is 23:59:59
... one second later it's 00:00:00
Time is 19:12:27
... one second later it's 19:12:28
Program ended with exit code: 0
结构中的结构
struct dateAndTime{
struct date sdate;
struct time stime;
}
嵌套的结构
struct rectangle{
struct point pt1;
struct point pt2;
};
//如果有变量
struct rectangle r;
//就可以有：
r.pt1.x = 1;
r.pt1.y = 2;
r.pt2.x = 11;
r.pt2.y = 22;
//如果有变量定义
struct rectangle *rp;
rp = &r;
//那么这四种形式是等价的
//r.pt1.x , rp->pt1.x, (r.pt1).x, (rp->pt1).x
//但是没有rp->pt1->x 因为pt1不是指针