Having issues when I'm running this python code on idle and can't figure out why. I'm thinking it has to do with the random numbers or the % int functions. def main(): import random # Generate a random integer between 10 and 100 to denote the initial size of the pile.  numOfMarbles = random.randint(10, 100) print("The size of the pile is:"), numOfMarbles # Generate a random integer between 0 and 1 to decide wheter the computer or the human takes the first turn.  turn = random.randint(0, 1) if turn == 0: print("Its the turn of a computer") else: print("Its your turn") # Generate a random integer between 0 and 1 to decide whether the computer plays smart or stupid.  stupidComputer = random.randint(0, 1) if stupidComputer == 0: print("Vs Smart computer") else: print("Vs Dumb computer") # In stupid mode the computer simply takes a random legal value (between 1 and n/2)  # from the pile whenever it has a turn.  while numOfMarbles != 1: # Till you're left with only one marble.  if turn == 0: # Computer turn  if stupidComputer == 1: # If the computer is playing in stupid mode.  temp = random.randint(1, numOfMarbles / 2) # Select a random number between 1, and n/2.  else: # Select the marbles smartly.  if numOfMarbles - 3 > 0 and numOfMarbles - 3 < int(numOfMarbles / 2): temp = numOfMarbles - 3 elif numOfMarbles - 7 > 0 and numOfMarbles - 7 < int(numOfMarbles / 2): temp = numOfMarbles - 7 elif numOfMarbles - 15 > 0 and numOfMarbles - 15 < int(numOfMarbles / 2): temp = numOfMarbles - 15 elif numOfMarbles - 31 > 0 and numOfMarbles - 31 < int(numOfMarbles / 2): temp = numOfMarbles - 31 else: temp = numOfMarbles - 63 print("The computer picked: %d marbles." % temp) # Print the marbles picked by computer.  numOfMarbles -= temp # Subtract the marbles picked by computer.  else: marblesToPick = int(input("Its your turn. Pick the marbles in the range 1 - %d: ")) % int(numOfMarbles / 2) # Read the marbles to be picked.  while marblesToPick < 1 or marblesToPick > int(numOfMarbles / 2): # If read invalid value, try repeatedly.  marblesToPick = input("You picked the wrong count. Pick the marbles in the range 1 - %d: ") % int(numOfMarbles / 2) numOfMarbles -= marblesToPick # Subtract the marbles picked by you.  turn = (turn + 1) % 2 # Change the turn.  print("the pile is of size %d.") % numOfMarbles if turn == 0: # Declare the result.  print("You won.") else: print("The computer won") main()