# 指针数组和二级指针

先看代码

```c
#include <stdio.h>
#include <stdlib.h>

int main(){
    char *lines[5] = {
        "wangyuedong0",
        "wangyuedong1",
        "wangyuedong2",
        "wangyuedong3",
        "wangyuedong4"
    };
    char *str1 = lines[1];
    char *str2 = *(lines + 3);
    char c1 = *(*(lines+1)+6);
    char c2 = (*lines+5)[5];
    char c3 = *lines[0] + 2;
    
    priintf("str1 = %s\n", str1);
    printf("str2 = %s\n", str2);
    printf("c1 = %c\n", c1);
    printf("c2 = %c\n", c2);
    printf("c3 = %c\n", c3);
    
    system("pause");
    return 0;
}
```

为了方便说明问题，我们将上面的字符串数组改成下面的形式，它们都是等价的。

```c
#include <stdio.h>
#include <stdlib.h>

int main(){
    char *string0 = "wangyuedong0";
    char *string1 = "wangyuedong1";
    char *string2 = "wangyuedong2";
    char *string3 = "wangyuedong3";
    char *string4 = "wangyuedong4";
    
    char *lines[5];
    lines[0] = string0;
    lines[1] = string1;
    lines[2] = string2;
    lines[3] = string3;
    lines[4] = string4;
    
    char *str1 = lines[1];
    char *str2 = *(lines+3);
    char c1 = *(*(lines+4)+6);
    char c2 = (*lines+5)[5];
    char c3 = *lines[0]+2;
    
    priintf("str1 = %s\n", str1);
    printf("str2 = %s\n", str2);
    printf("c1 = %c\n", c1);
    printf("c2 = %c\n", c2);
    printf("c3 = %c\n", c3);
    
    system("pause");
    return 0;
}
```






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