1、从键盘上输入字符，判别其分类：控制符、数字、大写字母、小写字母、其他字符
main( )
{ char c;
c=getchar( );
if (c< 32)
printf(“This is a control character.\n”);
else if (c>=‘0’&&c<=‘9’)
printf (“This if a digit.\n”);
else if (c>=‘A’&&c<=‘Z’)
printf (“This is a capital letter.\n”);
else if (c>=‘a’&&c<=‘z’)
printf (“This is a small letter.\n”);
else
printf (“This is an other charater.\n”);
}
