C语言篇 -(1)初识C语言 - (11)指针,结构体
指针
内存
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0001
0000 0000 0000 0000 0000 0000 0000 0010
…………
1111 1111 1111 1111 1111 1111 1111 1110
1111 1111 1111 1111 1111 1111 1111 1111
4,294,967,296byte
4,294,967,296÷1024=4,194,304kb
4,194,304÷1024=4,096MB
4,096÷1024=4GB
int main()
{
int a = 0;
&a;
return 0;
}
int main()
{
int a = 10;
int* p = &a;
return 0;
}
int main()
{
char a = 'w';
char* p = &a;
return 0;
}
#include<stdio.h>
int main()
{
int a = 10;
int* p = &a;
*p = 20;//这里的*p其实就相当于a了
//打印a的地址和a的值
printf("%p\n", p);//打印地址用%p
printf("%d\n", a);
return 0;
}
指针变量的大小
int main()
{
printf("%zu\n", sizeof(char*));
printf("%zu\n", sizeof(short*));
printf("%zu\n", sizeof(int*));
printf("%zu\n", sizeof(long*));
printf("%zu\n", sizeof(float*));
printf("%zu\n", sizeof(double*));
return 0;
}
int a = 10;
int* p = &a;
int *p = &a;
int* p1, p2, p3;
int *p1, p2, p3;
int *p1, *p2, *p3;