#include <stdio.h>
#include <stdlib.h>
char buff1[61];
char buff2[61];
void modify(char* ptr)
{
    while (*(ptr + 1) != *ptr && *(ptr + 1) != '\0')
    {
        *(ptr + 1) = *ptr;
        ptr++;
    }
}
void better_modify(char* ptr)
{
    char first = ptr[0];
    while (*ptr != '\0' && *(ptr + 1) != '\0')
    {
        while (*ptr == first)
        {
            ptr++;
        }
        while (*ptr != first && *(ptr + 1) != '\0')
        {
            ptr++;
        }
        modify(ptr);
    }
}
int input(int index)
{
    printf("\n\n==== INPUT ====\n\n");
    if (index == 1)
    {
        gets_s(buff1, 61);
        if (buff1[0] == '\0')
        {
            return 3;
        }
        return 1;
    }
    if (index == 2)
    {
        gets_s(buff2, 61);
        if (buff2[0] == '\0')
        {
            return 3;
        }
        return 2;
    }
}
int output(int index)
{
    printf("\n\n==== OUTPUT ====\n\n");
    if (index == 1)
    {
        puts(buff1);
        return 2;
    }
    if (index == 2)
    {
        puts(buff2);
        return 1;
    }
}
void main()
{
    int check = input(1);
    while (check != 3)
    {
        if(check==1)
        {
            modify(&buff1);
            better_modify(&buff1);
        }
        if(check==2)
        {
            modify(&buff2);
            better_modify(&buff2);
        }
        check = output(check);
        check = input(check);
    }
    system("pause");
}