[Codewars] Connect Four

Codewars: Achieve mastery through challenge

▶  문제 : 

▶  내 답안 :  시간초과로 실패

import pandas as pd 

def sameguys(con4) :
    r = ['Red','Red','Red','Red']
    y = ['Yellow', 'Yellow', 'Yellow','Yellow']
    if con4 == r :
        return "Red"
    elif con4 == y :
        return "Yellow"         
    
def who_is_winner(pieces_position_list):
    cols = 'A B C D E F G'.split()
    x = 4
    while True :
        if x >= len(pieces_position_list) :
            return 'Draw'
            break
        else :
            x+=1
            ppl = pieces_position_list[:x]
            c4_df = pd.DataFrame(columns=range(7), index=range(6))
            for i, v in enumerate(cols) :
                globals()[v] = [j.split('_')[1] for j in ppl if j.split('_')[0] == v]
                c4_df[i] = globals()[v] + [None]*(6-len(globals()[v]))
            for i in range(7) :
                for j in range(6) :
                    try :
                        a = sameguys([c4_df[i][j], c4_df[i+1][j], c4_df[i+2][j], c4_df[i+3][j]])
                        b = sameguys([c4_df[i][j], c4_df[i][j+1], c4_df[i][j+2], c4_df[i][j+3]])
                        c = sameguys([c4_df[i][j], c4_df[i+1][j+1], c4_df[i+2][j+2], c4_df[i+3][j+3]])
                        d = sameguys([c4_df[i+3][j], c4_df[i+2][j+1], c4_df[i+1][j+2], c4_df[i][j+3]])
                        if a in ['Red',"Yellow"] :
                            return(a)
                            break
                        if b in ['Red',"Yellow"] :
                            return(b)
                            break
                        if c in ['Red',"Yellow"] :
                            return(c)
                            break
                        if d in ['Red',"Yellow"] :
                            return(d)
                            break
                    except :
                        pass

▶  모범답안 : 

import numpy as np
from scipy.signal import convolve2d
def who_is_winner(ppl):
    arr = np.zeros((7,6), int)
    for a in ppl :
        pos, color = a.split('_')
        pos = ord(pos) - ord('A')
        val = (-1,1)[color == 'Red']
        arr[pos, np.argmin(arr[pos] != 0)] = val
        t_arr = val * arr
        if any(np.max(cv) == 4 for cv in(convolve2d(t_arr, [[1,1,1,1]], 'same'),
                                         convolve2d(t_arr, [[1],[1],[1],[1]], 'same'),
                                         convolve2d(t_arr, [[1,0,0,0],[0,1,0,0],[0,0,1,0],[0,0,0,1]], 'same'),
                                         convolve2d(t_arr, [[0,0,0,1],[0,0,1,0],[0,1,0,0],[1,0,0,0]], 'same'))) :
            return color
    return 'Draw'

 

 

▶  배워야할 부분 : any( ), ord( ), np.argmin( ), np.zeros( ), np.max( ), convolve2d(),ㅣ

                           val = (-1,1)[color == 'Red']

 

# pos : position

1. ord(), chr()  
# 아스키코드변환

ord('A')
>>> 65
chr(65)
>>> 'A'

2. pos = ord(pos) - ord('A')
for문을 돌면서 position 설정

A_Yellow  = 0
B_Yellow  = 1
C_Yellow  = 2


3. val = (-1,1)[color == 'Red']

(-1,1)[False]
>>> -1
(-1,1)[True]
>>> 1

4. arr[pos, np.argmin(arr[pos] != 0)] = val
> 각 리스트의 0이 아닌 최소 인덱스에 val를 할당해라
 
ppl = [ 'A_Yellow', 'B_Red', 'B_Yellow']
arr

>>> array([[-1,  0,  0,  0,  0,  0],
           [ 1, -1,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0]])

ppl = [ 'A_Yellow', 'B_Red', 'B_Yellow', 'C_Red']
arr

>>> array([[-1,  0,  0,  0,  0,  0],
           [ 1, -1,  0,  0,  0,  0],
           [ 1,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0],
           [ 0,  0,  0,  0,  0,  0]])
       

5. t_arr = val * arr 해주는 이유 :
	arr 안의 -1 값인 "Yellow"를 1로 뒤집어 주기 위해

ppl = [ 'A_Yellow', 'B_Red', 'B_Yellow']

>>> arr
array([[-1,  0,  0,  0,  0,  0],
       [ 1, -1,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0]])
       
>>> t_arr
array([[ 1,  0,  0,  0,  0,  0],
       [-1,  1,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0],
       [ 0,  0,  0,  0,  0,  0]])
       
6. np.max()


7. convolve2d()

8. any()

9. if any(np.max(cv) == 4 for cv in(
        convolve2d(t_arr, [[1,1,1,1]], 'same'),
        convolve2d(t_arr, [[1],[1],[1],[1]], 'same'),
        convolve2d(t_arr, [[1,0,0,0],[0,1,0,0],[0,0,1,0],[0,0,0,1]], 'same'),
        convolve2d(t_arr, [[0,0,0,1],[0,0,1,0],[0,1,0,0],[1,0,0,0]], 'same'))) :
      return color