#include<stdio.h>
#include<ctype.h>
int main(){
    char ch;
    scanf("%c",&ch);
    if(isalpha(ch)){
        printf("alphabet\n")
    }
    else if(isdigit(ch)){
        printf("digit\n");
    }
    else{
        printf("special character\n");
    }
    return 0;
    }