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# The Computer Language Benchmarks Game
# http://shootout.alioth.debian.org/
#
# contributed by Daniel Nanz, 2008-08-21

import optparse
import time
from bisect import bisect

import util

w, h = 5, 10
dir_no = 6
S, E = w * h, 2
SE = S + (E / 2)
SW = SE - E
W, NW, NE = -E, -SE, -SW


def rotate(ido, rd={E: NE, NE: NW, NW: W, W: SW, SW: SE, SE: E}):
    return [rd[o] for o in ido]

def flip(ido, fd={E: E, NE: SE, NW: SW, W: W, SW: NW, SE: NE}):
    return [fd[o] for o in ido]


def permute(ido, r_ido):
    ps = [ido]
    for r in range(dir_no - 1):
        ps.append(rotate(ps[-1]))
        if ido == r_ido:                 # C2-symmetry
            ps = ps[0:dir_no//2]
    for pp in ps[:]:
        ps.append(flip(pp))
    return ps


def convert(ido):
    '''incremental direction offsets -> "coordinate offsets" '''
    out = [0]
    for o in ido:
        out.append(out[-1] + o)
    return list(set(out))


def get_footprints(board, cti, pieces):
    fps = [[[] for p in range(len(pieces))] for ci in range(len(board))]
    for c in board:
        for pi, p in enumerate(pieces):
            for pp in p:
                fp = frozenset([cti[c + o] for o in pp if (c + o) in cti])
                if len(fp) == 5:
                    fps[min(fp)][pi].append(fp)
    return fps


def get_senh(board, cti):
    '''-> south-east neighborhood'''
    se_nh = []
    nh = [E, SW, SE]
    for c in board:
        se_nh.append(frozenset([cti[c + o] for o in nh if (c + o) in cti]))
    return se_nh


def get_puzzle(w=w, h=h):
    board = [E*x + S*y + (y%2) for y in range(h) for x in range(w)]
    cti = dict((board[i], i) for i in range(len(board)))

    idos = [[E, E, E, SE],         # incremental direction offsets
            [SE, SW, W, SW],
            [W, W, SW, SE],
            [E, E, SW, SE],
            [NW, W, NW, SE, SW],
            [E, E, NE, W],
            [NW, NE, NE, W],
            [NE, SE, E, NE],
            [SE, SE, E, SE],
            [E, NW, NW, NW]]

    perms = (permute(p, idos[3]) for p in idos)    # restrict piece 4
    pieces = [[convert(pp) for pp in p] for p in perms]
    return (board, cti, pieces)


def print_board(board, w=w, h=h):
    for y in range(h):
        for x in range(w):
            print(board[x + y * w])
        print('')
        if y % 2 == 0:
            print('')
    print()


board, cti, pieces = get_puzzle()
fps = get_footprints(board, cti, pieces)
se_nh = get_senh(board, cti)


def solve(n, i_min, free, curr_board, pieces_left, solutions,
          fps=fps, se_nh=se_nh, bisect=bisect):
    fp_i_cands = fps[i_min]
    for p in pieces_left:
        fp_cands = fp_i_cands[p]
        for fp in fp_cands:
            if fp <= free:
                n_curr_board = curr_board[:]
                for ci in fp:
                    n_curr_board[ci] = p
                if len(pieces_left) > 1:
                    n_free = free - fp
                    n_i_min = min(n_free)
                    if len(n_free & se_nh[n_i_min]) > 0:
                        n_pieces_left = pieces_left[:]
                        n_pieces_left.remove(p)
                        solve(n, n_i_min, n_free, n_curr_board,
                              n_pieces_left, solutions)
                else:
                    s = ''.join(map(str, n_curr_board))
                    solutions.insert(bisect(solutions, s), s)
                    rs = s[::-1]
                    solutions.insert(bisect(solutions, rs), rs)
                    if len(solutions) >= n:
                        return
        if len(solutions) >= n:
            return
    return

SOLVE_ARG = 60

def main(n):
    times = []
    for i in range(n):
        t0 = time.time()
        free = frozenset(range(len(board)))
        curr_board = [-1] * len(board)
        pieces_left = list(range(len(pieces)))
        solutions = []
        solve(SOLVE_ARG, 0, free, curr_board, pieces_left, solutions)
        #print len(solutions),  'solutions found\n'
        #for i in (0, -1): print_board(solutions[i])
        tk = time.time()
        times.append(tk - t0)
    return times

if __name__ == "__main__":
    parser = optparse.OptionParser(
        usage="%prog [options]",
        description="Test the performance of the Float benchmark")
    util.add_standard_options_to(parser)
    options, args = parser.parse_args()

    util.run_benchmark(options, options.num_runs, main)