[問題] --i 和i--的不同
目前在看Cracking the Coding Interview
有一些問題想請教大家
這是用c語言寫的
其中有一題是這樣的
Q:Implement a function void reverse(char* str) in C
which reverse a null-terminated string.
Answer:
void reverse(char *str){
char* end=str;
char tmp;
if (str){
while(*end){ /*find end of the string */
++end;
}
--end; /* set on char back, since last char is null*/
/*swap characters from start of string with the end of the
*string, until the pointers meet in the middle. */
while (str <end) {
tmp = *str;
*str++ = *end;
*end-- = tmp;
}
}
}
我有兩個問題：
1. --end 和 end-- 是哪裡不同
2. str< end 是在比較位址的大小嗎 還是pointer 在位址的先後順序
問很基礎的問題，真是不好意思 :p
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