python - What can I do to make this code work? -

i'm computer science student , of our classes used java , we're taking 1 have use python, hoping tell me why grid[i][j].append('q') never takes effect , can make work. purpose behind assignment generate 8 queens puzzle instances , return solutions. please me, here have far:

import pprint import random grid = [['-']*8 n in range(8)] insertpoint = random.randrange(1,8) in grid:     j in grid:         if i==insertpoint:             grid[i][j].append('q') pprint.pprint(grid) 

modification: want have q printed in separate column each time.

so tweaked code bit printed column problem it's printing in same column each time, reason using random try in separate 1 each time. here's code that's @ least letting me print in 1 column:

import pprint import random grid = [['-']*8 n in range(8)] insertpoint = random.randrange(1,8) in range(8):     j in range(8):         if j==insertpoint:             grid[i][j]=('q')   pprint.pprint(grid)      

i'm assuming have increment j somewhere between 2 loops , i've tried putting in different places not working.

i think got it, had move insertpoint variable loop

i'm close want code dave below i'd prefer output not have 'q's in same row. can please me, tried bunch of different stuff further away it

here's code , output:

import pprint import random grid = [['-']*8 n in range(8)] insertpoint = random.randrange(1,8) in range(0,8):     j in range(0,8):         if i==insertpoint:             grid[i][j] = 'q' pprint.pprint(grid)      [['-', '-', '-', '-', '-', '-', '-', '-'],      ['-', '-', '-', '-', '-', '-', '-', '-'],      ['-', '-', '-', '-', '-', '-', '-', '-'],      ['q', 'q', 'q', 'q', 'q', 'q', 'q', 'q'],      ['-', '-', '-', '-', '-', '-', '-', '-'],      ['-', '-', '-', '-', '-', '-', '-', '-'],      ['-', '-', '-', '-', '-', '-', '-', '-'],      ['-', '-', '-', '-', '-', '-', '-', '-']] 

in code, i , j not iterate on integers cannot used index array.

you try:

grid = [['-']*8 n in range(8)] insertpoint = random.randrange(1,8) in range(8):     j in range(8):         if i==insertpoint:             grid[i][j] = 'q';