c++ - 关于C语言char*指针的问题

Question

代码如下：

#include<stdio.h>

int main(void)
 {
     char* p = "xxx";

    printf("%c",*p);
    return 0;
}

为啥一定要加*号才能正确显示字符串的第一个字符呢？
不是p指针存了这个字符串了吗？
本人刚学C没多久，请大神们解析得仔细点，谢谢

Answer 1

First of all, I suggest you use an editor to debug, put a breakpoint on the printf line, and then look in the monitor to see what p and *p point to respectively.
Then, p is a character pointer type, pointing to the address of the first element of a character array, *p takes the value pointed to by p, which is the first element.
If you understand, you can think about the results of p++,*p++, and what is the value of p after the operation

Answer 2

First of all, there is no such type of string in C. Strings in C are character arrays terminated by null characters.
Then, the p pointer saves not the string, but the head of the character array. The address of the element.
So you can use the indirect operator * to read the value in this address, which is the first element of this character array.

Answer 3

Because the type of p here is a pointer, the string xxx is stored in the memory address it points to. If you use p directly, the output is the memory address pointed to by p. Add an * in front of it to output The content pointed to by this pointer.

Answer 4

First of all, p is a pointer type, which stores an address, and this address is index, which can be understood as the address of the first character of the entire string (actually not a string) , similar to the first element in an array. *This symbol refers to defining a pointer variable when it is defined, and when it is called, it takes the value in the address.
printf("%c",*p);, if you don’t add * to your statement, it means that what you output is the value of p, but the value of p is an address, so you will naturally not get the p address. The value that actually exists. By adding *, you can get the value stored at this address.

Answer 5

You can also add "*" without adding it. You can also use array subscript to output the first character

printf("%c",p[0]);

Answer 6

p is a pointer type. It stores the address pointing to the element. If is not added, the specific address is printed. After adding the sign, it is the element pointed to