accumulator

#include <stdio.h>
#include <ctype.h>

short get_operand(char mode) {
    short operand;
    switch(mode) {
        case 'O':
            printf("Enter octal value: ");
            scanf(" %o", &operand);
            break;
        case 'H':
            printf("Enter hexadecimal value: ");
            scanf(" %hx", &operand);
            break;
        case 'D':
        default:
            printf("Enter decimal value: ");
            scanf(" %d", &operand);
            break;
    }
    return operand;
}

void print_acc(short acc) {
    printf("\n");
    printf("**************************************\n");
    printf("* Accumulator:                       *\n");
    printf("*   Hex     :  %04hX                  *\n", acc);
    printf("*   Octal   :  %06ho                *\n", acc);
    printf("*   Decimal :  %-5d                 *\n", acc);
    printf("**************************************\n");
}

char print_menu() {
    printf("\n");
    printf("Please enter your command:\n");
    printf("\n");
    printf("D   Decimal Mode\n");
    printf("O   Octal Mode\n");
    printf("H   Hexadecimal Mode\n");
    printf("\n");
    printf("C   Clear accumulator\n");
    printf("S   Set accumulator\n");
    printf("\n");
    printf("Q   Quit accumulator\n");

    printf("\n");
    printf("Command: ");

    char choice;
    scanf(" %c", &choice);
    return choice;
}

int main() {
    short accumulator = 0;
    char mode = 'D';

    while (1) {
        print_acc(accumulator);
        char input_char = toupper(print_menu());

        switch (input_char) {
            case '\n':
                break;
            case 'Q':
                return 0;
                break;
            case 'C':
                accumulator = 0;
                printf("accumulator cleared!\n");
                break;
            case 'S':
                accumulator = get_operand(mode);
                break;
            case 'D':
                mode = input_char;
                printf("Mode is decimal!\n");
                break;
            case 'O':
                mode = input_char;
                printf("Mode is octal!\n");
                break;
            case 'H':
                mode = input_char;
                printf("Mode is hexadecimal!\n");
                break;
            default:
                printf("Invalid input! :(\n");
                break;
        }
    }
    return 0;
}