Question

1）我在https://www.tutorialspoint.com/compile_c_online.php上测试了我的代码它以某种方式通过显示1,3,27,23,19的理想输出来工作但是也给了我错误信息，这很奇怪，因为我的所有函数都没有任何整数。谁能告诉我为什么显示错误的行是错误的？

2）我怀疑它与角色'未正确处理有关，但我不知道如何打印除%%和\\以外的所有特殊字符。有人可以指引我查看完整的清单吗？

编辑：我意识到实际上有2个逃脱字符我错了（在https://www.geeksforgeeks.org/escape-sequences-c/找到了正确的术语），这是单引号和双引号。除了这个清单之外还有吗？

#include <stdio.h>

int improvedCountWords(const char *str) {

    int size=0;
    int number=0;
    int length=0;
    while (str[size]!='\0'){
        if (str[size]==' ' || str[size]=='.' || str[size]=='\\' || str[size]=='*' || str[size]=='"'){
            if (length>0){
                number+=1;
                length=0;
            }

        }
        else if (str[size]=='-' || str[size]=="'"){
            if (length>0){
                length++;
            }

        }
        else{
            length++;
        }
        size++;
    }
    if (length>0){
        number++;
    }
    return number;
}


int main(){
    char s1[]="Panting heavily, he continues his exercises -- grepping, installing new packages, logging in as root, and writing replacements for two-year-old shell scripts in Python.";

    char s2[]="\" You'll know why Python is better than Perl... when you try to read your code *six* months from now ...\"";
    char s3[]="With Yoda strapped to his back, Luke climbs up one of the many thick vines that grow in the swamp until he reaches the Dagobah statistics lab.";

    int x1=improvedCountWords("Python");        
    int x2=improvedCountWords("Python is AWESOME");
    int x3=improvedCountWords(s3);
    int x4=improvedCountWords(s1);
    int x5=improvedCountWords(s2);


    printf("%d,%d,%d,%d,%d",x1,x2,x3,x4,x5);



    return 0;
}

Answer 1

您的指针为"'"，而int是str[size]比较中提升的==中的字符值。它在这一行并且没有得到妥善处理;

    else if (str[size]=='-' || str[size]=="'"){

您可能需要将其与此'\''进行比较;

    else if (str[size]=='-' || str[size]=='\''){

Answer 2

str[size]是一个字符，您将其与字符串文字进行比较 - "'" [编译器必须在此语句上发出警告] 。由于您希望将字符串str的字符与单引号'进行比较，因此您需要将其转义以使其不代表自身。使用转义字符\来执行此操作。因此它应该是：

str[size]=='\''

来自C标准＃6.4.4.4p3

单引号＆＃39;，双引号＆＃34;，问号？，反斜杠\和任意整数值可根据下表的转义序列表示：

   single quote '            \'
   double quote "            \"
   question mark ?           \?
   backslash \               \\
   octal character           \octal digits
   hexadecimal character     \x hexadecimal digits

警告：指针和整数以及转义字符之间的比较

2 个答案: