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#include <cstdio>
#include <iostream>
using namespace std;

int main() {
    char ch;

    while ((ch = getchar()) != EOF) {
        if (isalpha(ch)) {
            printf("%c is an alphabet.\n", ch);
        } else {
            printf("%c is not an alphabet.\n", ch);
        }
        ch = getchar();
    }

    return 0;
}