Codificação

#include <stdio.h>
#include <string.h>
#include <conio.h>
#include <stdlib.h>

#define TRUE 1

void Menu(char *option);
void MENU_Codificar(char *input);
void Read_Word(char *input);

int main() {
    char input[255], option;
    option = input[0] = '\0';

    while(TRUE) {
        Menu(&option);
        Read_Word(input);
        if(option == 'q')
            MENU_Codificar(input);

            //TODO: Menu de descodificar
    }
    return 0;
}

void Menu(char *option) {

    printf("\t\t Menu Principal\n");
    printf("\tq - Codificar\n");
    printf("\tw - Descodificar\n");
    while(*option != 'q' && *option != 'w') {
        fflush(stdin);
        *option = getch();
    }
    system("cls");
}


void MENU_Codificar(char *input) {
    char word_out[255];
    int idx, control, comp;

    comp = strlen(input);
    control = 1;
    for(idx=0; idx < comp;idx++, control++) {
        if(control % 2 != 0)
            word_out[idx] = *(input+idx);
        else
            word_out[comp-idx] = *(input+idx);
    }

    word_out[idx+1] = '\0';
    system("cls");
    printf("Palavra original: %s\n", input);
    printf("Palavra codificada: %s\n", word_out);
    system("cls");
}

void Read_Word(char *input) {

    printf("Palavra: ");
    gets(input);
    system("cls");
}