How to think like a Computer Scientist: 課後習題第十四章2-3

#-------------------------------------------------------------------------------
# Name:        module1
# Purpose:
#
# Author:      penglaixy
#
# Created:     31/08/2013
# Copyright:   (c) penglaixy 2013
# Licence:     <your licence>
#-------------------------------------------------------------------------------
import sys
#import string
import time
import random
import copy

def test(did_pass):
    '''print the result of a test '''
    linenum=sys._getframe(1).f_lineno
    if did_pass:
        msg = "Test at line{0} ok".format(linenum)
    else:
        msg = "Test at line{0} failed".format(linenum)
    print msg

def share_diagonal(x0,y0,x1,y1):
    dy = abs(y1-y0)
    dx = abs(x1-x0)

    return dy == dx

def col_clashed(bs, c):

    for i in range(c):
        if share_diagonal(i,bs[i],c,bs[c]):
            return True

    return False

def has_clashed(the_board):
    length = len(the_board)
    for i in range(1,length):
        if col_clashed(the_board, i):
            return True
    return False

def test_suite():
    rng = random.Random()
    bd = list(range(8))  #modify the parameter to get board size of 4,8,16
    num_found = 0
    tries = 0
    t0 = time.clock()
    fruit_list = []
    while num_found < 10:
        rng.shuffle(bd)
        tries += 1
        if not has_clashed(bd):
            if bd in fruit_list:
                continue
            fruit_list.append(copy.deepcopy(bd))
            t1 = time.clock()
            print ("Found solution {0} in {1:>4} tries time used: {2:.6f} seconds.".format(bd,tries,t1-t0))
            tries = 0
            num_found += 1
            t0 = t1
    print fruit_list

def main():
    test_suite()
    pass

if __name__ == '__main__':
    main()

>>> 
*** Remote Interpreter Reinitialized  ***
>>> 
Found solution [4, 6, 3, 0, 2, 7, 5, 1] in  273 tries time used: 0.003799 seconds.
Found solution [1, 5, 0, 6, 3, 7, 2, 4] in  405 tries time used: 0.005890 seconds.
Found solution [1, 6, 4, 7, 0, 3, 5, 2] in   91 tries time used: 0.001515 seconds.
Found solution [4, 6, 0, 3, 1, 7, 5, 2] in  896 tries time used: 0.013420 seconds.
Found solution [2, 4, 1, 7, 0, 6, 3, 5] in 1407 tries time used: 0.019014 seconds.
Found solution [6, 1, 5, 2, 0, 3, 7, 4] in   17 tries time used: 0.000559 seconds.
Found solution [1, 5, 7, 2, 0, 3, 6, 4] in  281 tries time used: 0.004027 seconds.
Found solution [3, 7, 0, 2, 5, 1, 6, 4] in   19 tries time used: 0.000532 seconds.
Found solution [0, 5, 7, 2, 6, 3, 1, 4] in 1962 tries time used: 0.026640 seconds.
Found solution [2, 4, 1, 7, 5, 3, 6, 0] in  250 tries time used: 0.003678 seconds.
[[4, 6, 3, 0, 2, 7, 5, 1], [1, 5, 0, 6, 3, 7, 2, 4], [1, 6, 4, 7, 0, 3, 5, 2], [4, 6, 0, 3, 1, 7, 5, 2], [2, 4, 1, 7, 0, 6, 3, 5], [6, 1, 5, 2, 0, 3, 7, 4], [1, 5, 7, 2, 0, 3, 6, 4], [3, 7, 0, 2, 5, 1, 6, 4], [0, 5, 7, 2, 6, 3, 1, 4], [2, 4, 1, 7, 5, 3, 6, 0]]
>>>