1 #include"stdio.h"
2 #include"conio.h"
3 #include<stdlib.h>
4 int main()
5 {
6 char ch1, ch2;
7 int i;
8 printf("请选择相应的操作:\n1:小写转换大写\n2:大写转换小写\n0:输入错误\n");
9 scanf_s("%d",&i);
10 printf("\n选择菜单i=%d:", i);
11 switch (i)
12 {
13 case 1:
14 printf("请输入小写字母ch1=");
15 getchar();//有缓冲流自动把getchar()填充
16 ch1 = getchar();
17 //getch(ch1);
18 printf("请输入小写字母ch2=");
19 getchar();
20 //scanf_s("%c",ch2);
21 ch2 = getchar();
22 ch1 = ch1 - 32;
23 ch2 = ch2 - 32;
24 printf("ch1=%c\n", ch1);
25 printf("ch2=%c\n", ch2);
26 system("pause");
27 break;
28 case 2:printf("\n请输入大写字母ch1=");
29 getchar();
30 ch1 = getchar();
31 printf("\n请输入大写字母ch2=");
32 getchar();
33 ch2 = getchar();
34 ch1 = ch1 + 32;
35 ch2 = ch2 + 32;
36 printf("ch1=%c\n", ch1);
37 printf("ch2=%c\n", ch2);
38 system("pause");
39 break;
40 default:printf("0:输入错误\n\n");
41 }
42 }
