title: How to create 10 random x, y coordinates in a grid using Python
body: <p>I need to create a 8x8 grid and distribute 10 coins in random positions on the grid. The problem I am facing is that the randint function will sometimes generate the same random co-ordinates and therefore only 9 or 8 coins are generated and placed on the grid. How can I make sure this doesn't happen? Cheers :) This is my code so far:</p>
  
  <pre><code>from random import randint
  
  grid = []
  #Create a 8x8 grid
  for row in range(8):
      grid.append([])
      for col in range(8):
          grid[row].append("0")
  
  #create 10 random treasure chests
      #problem is that it might generate the same co-ordinates and therefore not enough coins
  for coins in range(10):
      c_x = randint(0, len(grid)-1)
      c_y = randint(0, len(grid[0])-1)
      while c_x == 7 and c_y == 0:
             c_x = randint(0, len(grid)-1)
             c_y = randint(0, len(grid[0])-1)
      else:
          grid[c_x][c_y] = "C"
  
  for row in grid:
  print(" ".join(row))
  </code></pre>
  
  <p>I have included a while/else - as there must not be a coin in the bottom left corner of the grid</p>