这是一个C类。我有以下方法。基本上，如果原始单词以辅音开头，它需要一个单词和一个newWord，通过将第一个字母移动到结尾（在结束标点符号之前）并在字符串中添加“ay”来创建newWord。我的所有逻辑和案例都有效。我遇到的问题是，当我在最后通过char * newWord并打印时，该值仍然是原始单词。 另外，我自己定义了那些isConsonant和isCapital等方法。 EndPunc获取第一个结束标点符号的索引。
实施例： word =“猫？!!” newWord =“Atc？!!”
word =“apple” newWord =“appleay”
但是当我追踪newWord之后，它仍然是“猫？!!”或“苹果”。我做错了什么？
#include <stdio.h>
//#include <string.h>
#define MAXLENGTH 31
char word[31] = "Aat!??!";
char newWord[31] = "";
char* w = word; char* n = newWord;
int isConsonant(char c) // return 1 if consonant, 0 if vowel, -1 if neither
{
int i = 0;
while(i < 33)
{
if(c == 'a'-i || c == 'e'-i || c == 'i'-i || c == 'o'-i || c == 'u'-i)
return 0;
i+=32;
}
if(c >= 65 && c <= 122) // its a letter
return 1;
else return -1;
}
int isCapital(char c)
{
if(c >= 97 && c <= 122) // lowerCase
return 0;
else return 1; // capital
}
int isPunctuation(char c)
{
if(c == '!' || c == ',' || c == '.' || c == '?' || c == ';' || c == ':')
return 1;
return 0;
}
int endPuncIndex(int wordLength, char* word)
{
int index = wordLength;
word += wordLength-1;
while(isPunctuation(*word--))
index--;
return index;
}
int pigLatin(char* word, char* newWord)
{
int length = 0;
char* tempWord = word;
while(*tempWord++ != '\0')
if(++length > MAXLENGTH)
return -1;
tempWord = tempWord-length-1;
int puncIndex = endPuncIndex(length, word); // get index of last punctuation, if none, index will be length of string
if(isConsonant(*word) == 1) // first letter is consonant
{
char firstLetter = *tempWord;
char secondLetter = *(++tempWord);
tempWord++;
if(isCapital(firstLetter))
{
firstLetter += 32; // makes it lowercase, will need to move this to the end
if(isCapital(secondLetter) == 0) // if second letter isn't capital, make it capital
secondLetter -= 32;
}
int start = 0;
newWord = &secondLetter;
newWord++;
while(start++ < puncIndex-2) // go up to punct index (or end of String if no ending punct)
{
newWord = tempWord++;
newWord++;
}
newWord = &firstLetter;
newWord++;
}
else // vowel, just copies the word letter for letter, no insert or shifting
{
int start = 0;
while(start++ < puncIndex) // go up to punct index (or end of String if no ending punct)
{
newWord = tempWord++;
newWord++;
}
}
// add "ay"
newWord = "a";
newWord++;
newWord = "y";
newWord++;
//then add remaining punctuation
while(puncIndex++ < length)
{
newWord = tempWord++;
newWord++;
}
newWord = newWord-(length);
while(*newWord != '\0')
printf("%c",*(newWord++));
return length+3;
}
int main()
{
pigLatin(w,n);
printf("\n");
system("PAUSE");
return 0;
}
答案 0 :(得分：1)
您正在对纯粹的局部变量进行更改：
char firstLetter = *tempWord; /* these are both values not pointers */
char secondLetter = *(++tempWord);
更糟糕的是，您正在捕获指向这些局部变量的指针，然后修改它们而不是您想要修改的内存：
newWord = &firstLetter;
newWord++;
/* ... */
newWord = &secondLetter;
newWord++;
也许你的意思是：
*newWord = firstLetter; /* store the letter in the position */
答案 1 :(得分：0)
使用时：
firstLetter += 32;
您只需为本地变量指定一个值。之后你做了像
这样的事情newWord = &secondLetter;
获取局部变量的地址并将其分配给newWord。这似乎没有多大意义，因为newWord是你的字符串的地址，也就是字符串的第一个字符的地址。也许你想用
访问你单词的这个地方的字符值newWord [0] = secondLetter;
你没有在任何地方指定firstLetter和secondLetter的实际值，这就是你没有改变单词的原因。幸运的是，你最终设法用tempWord替换了newWord，所以你再次看到你原来的单词。这个地方不是唯一一个错误的地方，你有很多对newWord的分配看起来真的错了，大部分时间你都在改变指针而不是字符串的底层数据。
我怀疑你是否正确理解了如何使用指针。你应该看一个好的教程，例如http://pw1.netcom.com/~tjensen/ptr/pointers.htm
熟悉如何使用指针和字符串后，应该检查代码并轻松看到只更改指针而不是newWord的实际值。
答案 2 :(得分：0)
还有更多建议......但是，修改了代码的一些部分;使用文件比较器查看更改...
#include <stdio.h>
//#include <string.h>
#define MAXLENGTH 31
char word[31] = "Aat!\?\?!";
char newWord[31] = {0,};
char* gword = word;
char* gnewWord = newWord;
int isConsonant(char c) // return 1 if consonant, 0 if vowel, -1 if neither
{
int i = 0;
while (i < 33)
{
if (c == 'a' - i || c == 'e' - i || c == 'i' - i || c == 'o' - i || c
== 'u' - i)
return 0;
i += 32;
}
if (c >= 65 && c <= 122) // its a letter
return 1;
else
return -1;
}
int isCapital(char c)
{
if (c >= 97 && c <= 122) // lowerCase
return 0;
else
return 1; // capital
}
int isPunctuation(char c)
{
if (c == '!' || c == ',' || c == '.' || c == '?' || c == ';' || c == ':')
return 1;
return 0;
}
int endPuncIndex(int wordLength, char* word)
{
int index = wordLength;
word += wordLength - 1;
//while(isPunctuation(*word--))
while (isPunctuation(*word))
{
word--;
index--;
}
return index;
}
int pigLatin(char* word, char* newWord)
{
int length = 0;
char* tempWord = word;
while (*tempWord++ != '\0')
if (++length > MAXLENGTH)
return -1;
tempWord = tempWord - length - 1;
// get index of last punctuation, if none, index will be length of string
int puncIndex = endPuncIndex(length, word);
if (isConsonant(*word) == 1) // first letter is consonant
{
char firstLetter = *tempWord;
char secondLetter = *(++tempWord);
tempWord++;
if (isCapital(firstLetter))
{
firstLetter += 32; // makes it lowercase, will need to move this to the end
if (isCapital(secondLetter) == 0) // if second letter isn't capital, make it capital
secondLetter -= 32;
}
int start = 0;
*newWord = secondLetter;
newWord++;
while (start++ < puncIndex - 2) // go up to punct index (or end of String if no ending punct)
{
*newWord = *tempWord;
tempWord++;
newWord++;
}
*newWord = firstLetter;
newWord++;
}
else // vowel, just copies the word letter for letter, no insert or shifting
{
int start = 0;
while (start++ < puncIndex) // go up to punct index (or end of String if no ending punct)
{
*newWord = *tempWord;
tempWord++;
newWord++;
}
// add "ay"
*newWord = 'a';
newWord++;
*newWord = 'y';
newWord++;
}
//then add remaining punctuation
while (puncIndex++ < length)
{
*newWord = *tempWord;
newWord++;
tempWord++;
}
fprintf(stderr, "Modified word: %s", gnewWord);
return length + 3;
}
int main(void)
{
pigLatin(gword, gnewWord);
printf("\n");
// system("PAUSE");
return 0;
}