#include <ctype.h>
#include <stdio.h>
int main() {
char a=0;
scanf("%c",&a);
if (isalpha(a)) {
printf("YES");
}
else {
printf("NO");
}
return 0;
} #include <stdio.h>
int main()
{
char a ='a';
scanf("%c",&a);
if((a >='a' && a <= 'z') || (a >='A' && a <= 'Z'))
{
printf("YES");
}
else
{
printf("NO");
}
return 0;
} #include <stdio.h>
#include <ctype.h>
int main() {
printf(isalpha(getchar())?"YES":"NO");
return 0;
} #include <stdio.h>
int main() {
char ch;
while (scanf("%c", &ch) != EOF) {
getchar();
// char即chatacter的本质就是一个整数,只是通过ASCII编码使其映射到不同的字符
if (('A' <= ch && ch <= 'Z') || ('a' <= ch && ch <= 'z')) {
printf("YES\n");
} else {
printf("NO\n");
}
}
return 0;
}