import BitStringGAProblem

## For demonstration purposes only, you should not actually use this function ...
def allOnes(chr) :
    return len([x for x in chr.bitstring if x == '1'])


def createPatternMatchProblem(pattern):
### Input: pattern is a string of 0's and 1's (like 1101101)
###
### returns BitStrogGAProblem.BitStromgGAProblem(fitnessFunc, len)
###   where fitnessFunc is a function that takes as input a chromosome,
###   and returns the number of bits that are the same as pattern.
###   len should be the length of the pattern
###
###   see the allOnes function as an example of a fitness function
    return


def createNQueensProblem(n):
### Input: Size of a chess board n (you may assume n is a power of 2
###
### returns BitStrogGAProblem.BitStromgGAProblem(fitnessFunc, len)
###   where fitnessFunc is a function that takes as input a chromosome
###   representing a chess board, and returns the number of *non-conflicts*
###   on the board (that is, higher numbers == fewer conflicts == good == more fit,  
###   lower numbers == more conflicts == bad == less fit)
###
###   len should be n * lg n (since for a board of size n, we need lg n
###    bits to represent a single queen)
###
###  For example, for n = 4, a chromosome would consist of 8 bits.  The board:
###
###     Q...
###     ...Q
###     .Q..
###     ..Q.
###
###  Would have the representation 00110110 (since the queen in the first row is
###    in colum 0 (00), the queen in the second row is in column 3 (11), the queen in the
###    third row is in column 1 (01) and the queen in the last row is in column 2 (10)
###    last queen is in row 11 (3)
    return