Data-Structures-and-algorithms/ZorbishtHashing.cpp at master · aditya2499/Data-Structures-and-algorithms · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
#include <bits/stdc++.h>
using namespace std;

unsigned long long int ZobristTable[8][8][12];
mt19937 mt(01234567);

unsigned long long int randomInt()
{
	uniform_int_distribution<unsigned long long int>
								dist(0, UINT64_MAX);
	return dist(mt);
}

int indexOf(char piece)
{
	if (piece=='P')
		return 0;
	if (piece=='N')
		return 1;
	if (piece=='B')
		return 2;
	if (piece=='R')
		return 3;
	if (piece=='Q')
		return 4;
	if (piece=='K')
		return 5;
	if (piece=='p')
		return 6;
	if (piece=='n')
		return 7;
	if (piece=='b')
		return 8;
	if (piece=='r')
		return 9;
	if (piece=='q')
		return 10;
	if (piece=='k')
		return 11;
	else
		return -1;
}

void initTable()
{
	for (int i = 0; i<8; i++)
	for (int j = 0; j<8; j++)
		for (int k = 0; k<12; k++)
		ZobristTable[i][j][k] = randomInt();
}

unsigned long long int computeHash(char board[8][9])
{
	unsigned long long int h = 0;
	for (int i = 0; i<8; i++)
	{
		for (int j = 0; j<8; j++)
		{
			if (board[i][j]!='-')
			{
				int piece = indexOf(board[i][j]);
				h ^= ZobristTable[i][j][piece];
			}
		}
	}
	return h;
}

int main()
{
	char board[8][9] =
	{
		"---K----",
		"-R----Q-",
		"--------",
		"-P----p-",
		"-----p--",
		"--------",
		"p---b--q",
		"----n--k"
	};

	initTable();

	unsigned long long int hashValue = computeHash(board);
	printf("The hash value is	 : %llu\n", hashValue);

	//Move the white king to the left
	char piece = board[0][3];

	board[0][3] = '-';
	hashValue ^= ZobristTable[0][3][indexOf(piece)];

	board[0][2] = piece;
	hashValue ^= ZobristTable[0][2][indexOf(piece)];


	printf("The new hash value is : %llu\n", hashValue);

	// Undo the white king move
	piece = board[0][2];

	board[0][2] = '-';
	hashValue ^= ZobristTable[0][2][indexOf(piece)];

	board[0][3] = piece;
	hashValue ^= ZobristTable[0][3][indexOf(piece)];

	printf("The old hash value is : %llu\n", hashValue);

	return 0;
}