ShellLiteChessEngine/perft_utils.shl at main · ShellLite/ShellLiteChessEngine · 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
to perft board depth
    if depth == 0
        give [1, 0, 0, 0, 0, 0, 0, 0, 0]

    n = 0
    c = 0
    ep = 0
    ca = 0
    pr = 0
    ch = 0
    disc = 0
    dbl = 0
    cm = 0

    moves = generate_legal_moves(board)
    for m in moves
        is_cap = no
        if m.captured != 0
            is_cap = yes

        is_ep = no
        if m.flags == 2
            is_ep = yes

        is_cas = no
        if m.flags == 4
            is_cas = yes

        is_pro = no
        if m.flags == 8
            is_pro = yes

        board.make_move(m)
        sub_stats = perft(board, depth - 1)

        n = n + sub_stats[0]
        c = c + sub_stats[1]
        ep = ep + sub_stats[2]
        ca = ca + sub_stats[3]
        pr = pr + sub_stats[4]
        ch = ch + sub_stats[5]
        disc = disc + sub_stats[6]
        dbl = dbl + sub_stats[7]
        cm = cm + sub_stats[8]

        if depth == 1
            if is_cap
                c = c + 1
            if is_ep
                ep = ep + 1
            if is_cas
                ca = ca + 1
            if is_pro
                pr = pr + 1

            opp_color = board.turn
            if is_in_check(board, opp_color)
                ch = ch + 1

                ksq = board.get_king_square(opp_color)
                my_color = 24 - opp_color
                attackers = get_attackers(board, ksq, my_color)

                if len(attackers) >= 2
                    dbl = dbl + 1
                else
                    att_sq = attackers[0]
                    if att_sq != m.to_sq
                        disc = disc + 1

                opp_moves = generate_legal_moves(board)
                if len(opp_moves) == 0
                    cm = cm + 1

        board.undo_move()

    give [n, c, ep, ca, pr, ch, disc, dbl, cm]

to real_perft board depth
    say "Wait..."
    total_nodes = 0
    moves = generate_legal_moves(board)
    for m in moves
        board.make_move(m)
        sub_stats = perft(board, depth - 1)
        say move_to_str(m) + ": " + str(sub_stats[0])
        total_nodes = total_nodes + sub_stats[0]
        board.undo_move()
    say ""
    say "Nodes searched: " + str(total_nodes)
    give total_nodes