习题5.7

#include <stdio.h>#include <stdlib.h>int main(){    char ch;    printf("请输入一个英文字母");    scanf("%c",&ch);    if(ch>='A'&&ch<='Z')    {    ch=ch+32;    printf("%c %d\n",ch,ch);    }    if(ch>='a'&&ch<='z')    {       ch=ch-32;    printf("%c %d\n",ch,ch);    }    else    printf("%d\n",ch);return 0;}