C中的++ * p,* p ++和* ++ p之间的区别
指针式
在C语言中,*p表示存储在指针中的值。++是前缀和后缀表达式中使用的增量运算符。*是取消引用运算符。前缀++和*的优先级相同,并且两者从右到左关联。后缀++的优先级高于前缀++和*,并且从左到右具有关联性。请参见以下示例,以了解++*p,*p++和*++p之间的区别。
范例(C)
#include <stdio.h>
int main() {
int arr[] = {20, 30, 40};
int *p = arr;
int q;
//value of p (20) incremented by 1
//and returned
q = ++*p;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d \n",
arr[0], arr[1], *p, q);
//value of p (20) is returned
//pointer incremented by 1
q = *p++;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d \n",
arr[0], arr[1], *p, q);
//pointer incremented by 1
//value returned
q = *++p;
printf("arr[0] = %d, arr[1] = %d, *p = %d, q = %d \n",
arr[0], arr[1], *p, q);
return 0;
}输出结果
arr[0] = 21, arr[1] = 30, *p = 21, q = 21 arr[0] = 21, arr[1] = 30, *p = 30, q = 21 arr[0] = 21, arr[1] = 30, *p = 40, q = 40
热门推荐
10 节日对老公祝福语简短
11 转给爱人红包祝福语简短
12 简短空间祝福语 搜
13 医院探望朋友祝福语简短
14 生活祝福语长辈的话简短
15 园长退休祝福语老师简短
16 校园周年庆祝福语简短
17 老妈花束祝福语大全简短
18 简短古诗词祝福语