import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class example {
    public static void main(String[] args) throws IOException {
        BufferedReader reader =
                new BufferedReader(new InputStreamReader(System.in));

        char lastSector = reader.readLine().charAt(0);
        int firstSectorRows = (Integer.parseInt(reader.readLine()));
        int placesInOddRow = (Integer.parseInt(reader.readLine()));
        int placesInEvenRow = placesInOddRow+2;
        int allPlace =0;

        for (int i = 65; i <= lastSector ; i++) {
            for (int j = 1; j <=firstSectorRows ; j++) {


                if (j%2==0){
                    for (int k = 97; k < 97 + placesInEvenRow; k++) {
                        char sector = (char)i;
                        int row = j;
                        char place = (char)k;
                       String stringForOutPut = String.format("%s%d%s",sector,row,place);
                        System.out.println(stringForOutPut);
                        allPlace++;
                    }
                }else {
                    for (int k = 97; k < 97 + placesInOddRow; k++) {

                        char sector = (char)i;
                        int row = j;
                        char place = (char)k;
                        String stringForOutPut = String.format("%s%d%s",sector,row,place);
                        System.out.println(stringForOutPut);
                        allPlace++;
                    }
                }
            }
            firstSectorRows++;

        }
        System.out.println(allPlace);

    }
}