数组删除c中的前3个字符

Question

我有这样的数据结构:

struct WordCounter
{
char *word;
int word_count;
struct WordCounter *pNext;                        /* Pointer to the next word counter in the list */
};

我需要它来记住从文件中读取的单词以及它们出现的次数。这个结构体有以下功能:

int giveCounter (struct WordCounter *pCounter){   // give the occurrence of the current word in the linked list
int tempcount = pCounter -> word_count;
return tempcount;

}
int lengthOfCurrentWord(struct WordCounter *pWordCounter) // length of the current string
{

return strlen(pWordCounter->word)+1;  // for the null terminator string 
}
char* giveWord(struct WordCounter *pWordcounter){  // return current word of the linked list
return pWordcounter->word;
}

我应该做的是，将列表中的所有单词放入一个数组中，每个单词用终止符分隔。代码是这样的，在我解释了问题在哪里之后:

pCounter = pStart; // go to the first element in the linked list
num_car=0;  // in total how much character in all words
while(pCounter != NULL){
num_car += lengthOfCurrentWord(pCounter);
pCounter = pCounter -> pNext;
}
printf("total number of chars in all words is: %d n ", num_car);

好了，现在我们有了大数组的维度，它必须保存所有以终止符分隔的单词。

char *exactly_word; // im forced to initialize like this and after i can  give the exactly number of elements
exactly_word = malloc(sizeof(char)*num_car); // The big array
memset(exactly_word,0,num_car);

让我们开始将链表中的单词复制到大数组中:

char wordy[100] = {0}; // an array for the temp word
pCounter = pStart;  // go to the first element
int indice = 0;   // used for loop through single word
int indice_parole = 0;  // It is used to indicate in which position of the large array to insert the character
for(int x=0; x<readed_nd_word;x++){   // readed_nd_words is the number of element in the linked list

strcat(wordy,giveWord(pCounter));  // copy the current word into wordy array
printf("WORDY: %s n",wordy);      // yeah correct in each iteration

while(wordy[indice]!= 0){
printf("Character to add to exactly word: %c, at position: %d n",wordy[indice],indice_parole);
exactly_word[indice_parole] = wordy[indice]; // copy character
indice_parole++;
indice++;
}

pCounter = pCounter -> pNext; // move into next word in the linked list
memset(wordy,0,100);   // reset for a new word
indice = 0;

exactly_word[indice_parole] =0; // terminator for separating words
printf("Terminator at position %d",indice_parole);
indice_parole++; 


}

问题在哪里?好的，在while循环中，exactly_word以正确的方式填充，但是在这段代码之后，如果我尝试打印exactly_word[0]，输出是:"，同样的位置1,2的exactly_word。我可以用一个例子更好地解释这个问题，我用输出来描述它:

words in the linked list:
wut   1
sut   1
ov   1
word   2
ciao   1
helo   1
cor   1
fal   1
vermalen   1
total number of chars in all words is: 43 (countered the terminator too)
WORDY: wut 
Character to add to exactly word: w, at position: 0
Character to add to exactly word: u, at position: 1
Character to add to exactly word: t, at position: 2
terminator at position 3
WORDY: sut 
Character to add to exactly word: s, at position: 4
Character to add to exactly word: u, at position: 5 
Character to add to exactly word: t, at position: 6 
terminator at position 7

对于其余的单词，输出是正确的，但是在这段代码之后，正如我所说的，如果我打印exactly_word[0]，我得到一个"，与1,2相同，而不是在exactly_word[4] = "源自单词sut。如果我打印所有的数组，我得到的是:"sutovwordciaohelocorfalvermalen"

注。错误并不是每次运行都会出现，有时会出现，有时不会，当错误没有完全出现时，单词就会被更正。是不是有什么我看不见的无防卫行为?请帮忙:

Answer 1

在评论中，您向我们展示了exactly_word的十六进制转储

01 00 00 00 73 75 74 00 6f 76 00 77 6f 72 64 ...

表示您覆盖了exactly_word的前3个(可能是4个)字节的内存。看起来整数值1已写入数组的开始(小端序)，但这只是一个猜测，因为:它不会发生在发布的代码。它一定是在你没有给我们看的代码里。

也就是说，你现在的代码太复杂了。简化如下:

exactly_word = malloc(num_car);
char* dst = exactly_word;
pCounter = pStart;
while(pCounter){
strcpy(dst, giveWord(pCounter));
dst += lengthOfCurrentWord(pCounter);  // which includes termination char
pCounter = pCounter -> pNext;
}