相关疑难解决方法(0)

我真的很困惑在字符串上使用指针.感觉他们遵守不同的规则.请考虑以下代码

1. char *ptr = "apple";// perfectly valid here not when declaring afterwards like next
   
   ptr = "apple"; // shouldn't it be *ptr = "apple"
   

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2. 也printf()表现不同-

   printf("%s", ptr) // Why should I send  the address instead of the value
   

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3. 我还在一本书中看到了以下代码

   char str[]="Quest";
   char *p="Quest";
   
   str++; // error, constant pointer can't change
   
   *str='Z'; // works, because pointer is not constant
   
   p++; // works, because pointer is not constant
   
   *p = 'M'; // error, because string is constant
   

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我无法理解应该暗示什么

请帮忙,我在其他地方找不到任何信息