求解 为什么会这样

#include<stdio.h>
int main()
{
char ch;
printf("please input a char:");
scanf("%c",&ch);
getchar();
while(!(ch>='A'&&ch<='Z'||ch>='a'&&ch<='z'));
{
printf("\aplease input a char:");
scanf("%c",&ch);
}
ch=(ch>='A'&&ch<='Z')?(ch+32):ch;
printf("%c\n",ch);
return 0;
}

while(!(ch>='A'&&ch<='Z'||ch>='a'&&ch<='z'));
将你这个循环后面的";"取消
while(!(ch>='A'&&ch<='Z'||ch>='a'&&ch<='z'))