Question

我正在编写以下代码来根据它们的长度来处理字符串，但是我得到了分段错误，用Google搜索它并发现它与指针相关但却无法找出相同的原因。

#include <string.h>
#include <iostream.h>
#include <stdio.h>

int main()
{
   char input[500];
   strcpy(input, "quick brown fox jumps on lazy dog");
   const char s[2] = " ";
   unsigned int num = 7;
   unsigned int lent;
   cin >> num;
   char *token;
   token = strtok(input, s);
   while( token != NULL ) 
   {
        lent= strlen(token);
        if(lent <= num)
            printf( " %s", token );
        token = strtok(NULL, s);
        if(strlen(token) <= (num-lent))
            printf("%s",token );
        printf("\n");
   }

   return(0);
}

Answer 1

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您到达输入字符串的末尾。此行token = strtok(NULL, s);变为token。但是，您会立即使用NULL。

在任何可能取消引用它的操作之前检查strlen(token)。

无法找到分段故障的原因

1 个答案: