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在編寫程序以在C中反轉字符串中的單詞時遇到麻煩

[英]Having trouble writing program to reverse words in string in C

我正在嘗試編寫一個小程序來反轉字符串中的單詞(經典面試問題),但是我遇到了一些麻煩。 在該網站的另一部分,我遇到了一種非常酷的方法,可以使用按位運算來將字符串反向轉換到適當的位置,因此,我嘗試使用僅利用單個reverse()的程序,該程序將反向轉換整個字符串,然后是子串。

不幸的是,我的程序只會反轉第一個子字符串,而我很難找出原因。 任何幫助將非常感激。

#include<stdlib.h>
#include<stdio.h>
#include<string.h>
void reverse(char string[], int beg, int end) {
  int length = end-beg-1;
  for(int i=beg; i < length/2; i++) {
    string[i] = string[i] ^string[length-i];
    string[length-i] = string[i] ^ string[length - i];
    string[i] = string[i] ^string[length-i];
  }

 }

int main (int argv, char * arrv[]) {
   int beg, end;
   char string[] = "This is the string to reverse";
   int length = strlen(string);
   printf("%s\n", string);
   printf("%d\n", length);
 //reverse whole string
   reverse(string, 0, length);
   printf("%s\n", string);
   beg =0;
   end = 0;
  //reverse strings at index's beg and end
    for(int i = 0; i <= length-1; i++) {
      if (string[i] == ' ') {                                      
       reverse(string, beg, end);
       beg = i+1;  
     }
     end++;
     printf("%s\n", string);
   }
   printf("%s\n", string);
    return 1;
}

謝謝IE預期輸出:反轉為字符串,這是我的輸出:反轉ot gnirts eht si siht

加上@alexd的建議,以下是已更新的程序,幾乎沒有修復:

#include<stdlib.h>
#include<stdio.h>
#include<string.h>
void reverse(char string[], int beg, int end) {
    int length = end - beg;
    for (int i = 0; i < length / 2; i++) {
        string[beg + i] = string[beg + i] ^ string[end - 1 - i]; 
        string[end - 1 - i] = string[beg + i] ^ string[end - 1 - i]; 
        string[beg + i] = string[beg + i] ^ string[end - 1 - i]; 
    }   
}

int main (int argv, char * arrv[]) {
   int beg, end;
   char string[] = "This is the string to reverse";
   int length = strlen(string);
   printf("%s\n", string);
   printf("%d\n", length);
 //reverse whole string
   reverse(string, 0, length);
   printf("%s\n", string);
   beg =0; 
   end = 0;
  //reverse strings at index's beg and end
    for(int i = 0; i <= length-1; i++) {
      if (string[i] == ' ') {    
       reverse(string, beg, end);
       beg = i+1;  
       printf("%s %d %d\n", string, beg, end);
     } else if(i==length-1) {
       end = length;
       reverse(string, beg, end);
     }   
     end++;
 }
   printf("%s\n", string);
    return 1;
}

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