Python Connect 4游戏-机载X版

Question

I am trying to create a connect four game but I cannot figure out how to print the checkers on the board. I need it to print the X at the lowest available spot in the column that the user inputted. Each time I run the program, I get the same blank 6 by 7 board. Please help. thank you!

#ConnectFour

numRows=6
numCols=7
numPlayers=2
board=[]
checkers=['X','O']
turn=0
win = False

for row in range(numRows):
    tempList=[]
    for col in range(numCols):
            tempList.append('.')
    board.append(tempList)

while not win:
    turn = (turn+1)%numPlayers

    userCol = input ("Player"+str(turn+1)+"please enter your col: ")
    while not userCol.isdigit() or not int(userCol) in range(numCols):
        userCol = input ("Player"+str(turn+1)+"please enter your col: ")

    for row in range(numRows):
        for col in range(numCols):
            print(board[row][col], end='')
        print()

    for repeat in range(numRows-2):
        for row in range(numRows,-1,-1):
            for col in range(numCols):
                if board[row][int(userCol)]==".":
                    board[row+1][int(userCol)]="X"
                    print
            break


#print board
for row in range(numRows):
    for col in range(numCols):
            print(board[row+1][userCol],end=' ')
    print()

print ("Player", checkers[turn],"has won the game.")

Answer 1

Here's what I noticed:

• Lines 24-27: This will print the unmodified board after a player drops a checker; perhaps this should be after lines 29-35 instead?
• Line 30: Looks like an off-by-one error, you might want range(numRows - 1, -1, -1) or reversed(range(numRows)) instead.
• Line 29: Why is it necessary to repeat the empty-space check?
• Line 31: What does this do? It iterates over each column, sure, but why is that necessary? You already know what column was requested, so why go over each column again?
• Lines 32-33: Seems to read "if the space is empty, place a checker in the slot below it". I'm thinking you probably want board[row][int(userCol)] = 'X' instead
• Line 41: Looks like another off-by-one error, row+1 should be row . Also, should userCol just be col ? Otherwise it'll only be printing one column instead of the entire final board.

General remarks:

Generally you can achieve more concise and readable python code by avoiding the for i in range(x): do_something(mylist[i]) anti-pattern and instead using python-style iteration: for item in mylist: do_something(item) .

I would re-write lines 29-35. But before you do so, ask yourself exactly what those lines are supposed to do. If I understand the task correctly, you should only need one for loop there.

Ninja edit: Also, once that's working, don't forget to handle the case that the player entered a valid column number, yet that column is completely filled, in which case you probably want to ask the same player to choose a new column.