#include<stdio.h>
#include<string.h>
char*mapping[]={
    "","","ABC","DEF","GHI","JKL","MNO","PQRS","TUV","WXYZ"};
    void generate(char digits[],int index,char current[],int len){
        if(index==len){
            printf("%s",current);
            return;
        }
        int digit=digits[index]-'0';
        char*letters=mapping[digit];
        for(int i=0;letters[i]!='\0';i++){
            current[index]=letters[i];
            current[index+1]='\0';
            generate(digits,index+1,current,len);
            if(!(index==len-1&&letters[i+1]=='\0'))
            printf(", ");
        }
    }
    int main(){
        char igits[20];
        scanf("%s", digits);
        int len =strlen(digits);
        if(len==1){
            int d=digits[0]-'0';
            printf("[");
            for(int i=0;mapping[d][i]!='\0'i++){
                printf("%c",mapping[d][i]);
                if(mapping[d][i+1]!='\0')
                printf("]");
                return 0;
            }
            char current[20]="";
            printf("[");
            generate(digits,0,current,len);
            printf("]");
            return 0;
        }
    }