程序:使用可变参数函数的概念进行字符串连接

#include <stdio.h>
#include <stdarg.h>

char* stringConcat(int count, ...) {
    va_list args;
    va_start(args, count);

    // 计算连接后字符串的总长度
    int totalLength = 0;
    for (int i = 0; i < count; i++) {
        char* str = va_arg(args, char*);
        totalLength += strlen(str);
    }

    // 创建一个足够容纳连接后字符串的字符数组
    char* result = (char*)malloc(totalLength + 1);
    result[0] = '\0'; // 确保字符串以'\0'结尾

    // 将每个字符串连接到结果字符串中
    va_start(args, count); // 重新初始化args
    for (int i = 0; i < count; i++) {
        char* str = va_arg(args, char*);
        strcat(result, str);
    }

    va_end(args);

    return result;
}

int main() {
    char* str1 = "Hello, ";
    char* str2 = "world!";
    char* str3 = " How are you?";

    char* result = stringConcat(3, str1, str2, str3);
    printf("%s\n", result);

    free(result);

    return 0;
}