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| //
// main.cpp
// TryXcode
//
// Created by ditsing on 10/19/13.
// Copyright (c) 2013 ditsing. All rights reserved.
//
#include <iostream>
#include <cstring>
using namespace std;
const int STEPS_L = 7;
int steps[STEPS_L][4] = {
{ 1, 0, 1, 0},
{ 1, 1, 0, 0},
{ 1, 0, 1, 0},
{ 1, 0, 0, 0},
{ 1, 0, 1, 0},
{ 1, 1, 0, 0},
{ 1, 0, 1, 0},
};
int coins[4];
int table[STEPS_L+1][4];
int tmp_table[4];
int rotat[STEPS_L];
int fail_count;
bool check_win( int coins[])
{
return coins[0] == coins[1] && coins[1] == coins[2] &&
coins[2] == coins[3];
}
int search_coins( int step)
{
if ( step == STEPS_L)
{
printf("Fails on Initial situation of %d %d %d %d.\n",
coins[0], coins[1], coins[2], coins[3]);
printf("Ends up with %d %d %d %d.\n",
table[step][0], table[step][1], table[step][2], table[step][3]);
printf("With rotation as %d %d %d %d %d %d.\n",
rotat[0], rotat[1], rotat[2], rotat[3],
rotat[4], rotat[5]);
return 1;
}
for ( int i( 0); i < 4; i++)
{
table[step+1][i] = table[step][i] ^ steps[step][i];
}
if ( check_win( table[step+1]))
{
printf("Wins on Initial situation of %d %d %d %d.\n",
coins[0], coins[1], coins[2], coins[3]);
printf("Ended up with %d %d %d %d at step %d.\n",
table[step+1][0], table[step+1][1], table[step+1][2], table[step+1][3],
step + 1);
printf("With rotation as %d %d %d %d %d %d %d.\n",
rotat[0], rotat[1], rotat[2], rotat[3],
rotat[4], rotat[5], rotat[6]);
printf("\n");
return 0;
}
int fail_count = 0;
for ( int ro = 0; ro < 2; ro++)
{
rotat[step] = ro;
for ( int i( 0); i < 4; i++)
{
tmp_table[(i+ro)&3] = table[step+1][i];
}
memcpy( table[step+1], tmp_table, sizeof( tmp_table));
fail_count += search_coins( step + 1);
}
rotat[step] = -1;
return fail_count;
}
int main(int argc, const char * argv[])
{
fail_count = 0;
for ( coins[0] = 0; coins[0] < 2; coins[0]++)
{
for ( coins[1] = 0; coins[1] < 2; coins[1]++)
{
for ( coins[2] = 0; coins[2] < 2; coins[2]++)
{
for ( coins[3] = 0; coins[3] < 2; coins[3]++)
{
memcpy( table, coins, sizeof( coins));
memset( rotat, 255, sizeof( rotat));
if ( !check_win( coins))
{
fail_count += search_coins( 0);
}
}
}
}
}
printf("Fails on %d cases.\n", fail_count);
return 0;
}
|