Question

我一直得到错误：“下标值既不是数组也不是指针也不是矢量”我第14行的代码。看起来它应该能够将数组中的值与char进行比较，因为它们是两个原始数据，但我似乎无法做到正确：

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

char str[80];
char ch;
int cnt =0;

int suffix ( str, ch) {

int i=0;

while (strchr(str+i, ch) != NULL){

    if (ch == str[i] ){
        printf("\n %s \n", str+i);
        cnt += 1;

    }

    i++;        

}
return cnt;
}

int main() {


printf("\n Please type a single character and then press ENTER: \n");
ch = getchar();
printf("\n You have typed in the character \" %c \".\n", ch);

printf("\n Now please enter a string. Press ENTER to confirm: \n");
scanf("%s", str);
printf("\n The String you typed in is: %s.", str);

suffix(str, ch);
printf("The character \" %c \" appeares %d times in the string. \n", ch, cnt);
return 0;

}

Answer 1

问题在于你宣布这样的功能：

int suffix ( str, ch)
{
    ...
}

没有告诉编译器str和ch的类型。所以编译器假定它们是int，您无法在[]上使用int。你必须申报像这样的功能

int suffix(char *str, char ch)
{
    ...
}

为什么要将str，ch和cnt声明为全局变量？有绝对没有理由。

所以程序看起来应该是这样的：

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

// const char is even better, because you are not modifying the string
int suffix (const char *str, char ch) {

    int cnt = 0;
    int i=0;

    while (strchr(str+i, ch) != NULL){

        if (ch == str[i] ){
            printf("\n %s \n", str+i);
            cnt += 1;

        }

        i++;        

    }
    return cnt;
}

void clean_stdin(void)
{
    int ch;
    while((ch = getchar()) != '\n' && ch != EOF);
}

int main() {

    int ch;
    int cnt;
    char str[100];

    printf("\n Please type a single character and then press ENTER: \n");
    ch = getchar();
    printf("\n You have typed in the character \" %c \".\n", ch);

    clean_stdin(); // to get rid of the newline in the input buffer
                   // or if the user typed more than a single character

    printf("\n Now please enter a string. Press ENTER to confirm: \n");
    scanf("%99s", str);
    printf("\n The String you typed in is: %s.", str);

    cnt = suffix(str, ch);
    printf("The character \" %c \" appeares %d times in the string. \n", ch, cnt);
    return 0;
}

无法将单个Char与Chars数组进行比较

1 个答案: