C语言统计字符串A在字符串B出现的次数

在C语言中，你可以使用循环结构和字符串处理函数来统计字符串A在字符串B中出现的次数。这里是一个简单的示例代码：

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

int count_occurrences(const char* strB, const char* substrA) {
    int count = 0;
    size_t lenB = strlen(strB);
    size_t lenA = strlen(substrA);

    for (size_t i = 0; i <= lenB - lenA; ++i) {
        if (strncmp(strB + i, substrA, lenA) == 0) { // 使用strncmp避免缓冲区溢出
            count++;
        }
    }

    return count;
}

int main() {
    const char* stringB = "Hello, how are you? I'm doing great!";
    const char* stringA = "are";
    
    int occurrences = count_occurrences(stringB, stringA);
    printf("String '%s' appears %d times in string '%s'.\n", stringA, occurrences, stringB);
    return 0;
}

这个`count_occurrences`函数会遍历字符串B，并通过`strncmp`函数比较子串是否匹配，如果匹配则计数加一。最后返回计数值。