用函数指针写100个字符串中$的个数

很高兴为您解答。以下是使用函数指针写100个字符串中$的个数的示例代码：

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

int count_char(char *str, char ch) {
    int count = 0;
    while (*str != '\0') {
        if (*str == ch) {
            count++;
        }
        str++;
    }
    return count;
}

int main() {
    char strings[100][100] = {
        "apple$pear",
        "hello!world$",
        "abcd$$efg",
        "1234",
        "$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$",
        "", // an empty string
        "$", // a string with only one $
        "shi$san$shi",
        "2$2=4",
        "#$%^&",
        "[[[[[[[[[[[[[[[[[[["
        // ... and so on for 90 more strings ...
    };
    int (*count_char_ptr)(char *, char) = &count_char;
    char ch = '$';
    int total_count = 0;
    for (int i = 0; i < 100; i++) {
        int count = count_char_ptr(strings[i], ch);
        printf("Count of %c in string %d: %d\n", ch, i+1, count);
        total_count += count;
    }
    printf("Total count of %c in all strings: %d\n", ch, total_count);
    return 0;
}

该程序声明了一个二维字符数组`strings`，其中包含了100个字符串；以及一个指向函数`count_char`的函数指针`count_char_ptr`。在`main`函数中，通过循环遍历每个字符串，使用函数指针`count_char_ptr`计算每个字符串中字符`'$'`的个数，并输出结果。最后，程序计算所有字符串中字符`'$'`的总数，并输出结果。

如果您有任何问题，欢迎随时提出。