新手这个是把这两个字符组合在一起的

#include "stdio.h"
void main()
{
	char str1[] = "I love you！";
	char str2[] = "Do you？";
	int i = 0;
	for (i = 0; str1[i]; i++);
	int j = 0;
	for (j = 0; str2[j]; j++);
	{
		str1[i] = str2[j];
		i++;
	}
	str1[i] = '\0';
	printf("%s", str1);
}