#include<stdio.h>
#include<string.h>
int main()
{
int i=0;
char g;
char str1[50] = { "Welcome to GDUT," };
char str2[] = { "my friend" };
while (i <= 15)//-----------------------循环加switch语句进行各字符串函数的操作，有疑问：为什么要循环十五次才能出现6个结果？
{
scanf_s("%c", &g, sizeof(g));
switch (g)
{
case'A':printf("%s", strcat(str1, str2));break;
case'B':printf("%s", strncat(str1, str2, 2));break;
case'C':printf("%s", strcpy(str1, str2));break;
case'D':printf("%s", strncpy(str1, str2, 2));break;
case'E':printf("str2字符串长度为%d", strlen(str2));break;
case'F':printf("%d", strcmp(str1, str2));break;
default:putchar('\a');
}
i++;
}
return 0;
}