#P1468. [IOI 1998 / USACO2.2] Party Lamps

[IOI 1998 / USACO2.2] Party Lamps

题目描述

To brighten up the gala dinner of the IOI'98 we have a set of NN (10N10010 \le N \le 100) colored lamps numbered from 11 to NN.

The lamps are connected to four buttons:

  • Button 11: When this button is pressed, all the lamps change their state: those that are ON are turned OFF and those that are OFF are turned ON.
  • Button 22: Changes the state of all the odd numbered lamps.
  • Button 33: Changes the state of all the even numbered lamps.
  • Button 44: Changes the state of the lamps whose number is of the form 3k+13k+1 (with k0k \ge 0), i.e., 1,4,7,1,4,7,\ldots.

A counter CC records the total number of button presses.

When the party starts, all the lamps are ON and the counter CC is set to zero.

You are given the value of counter CC (0C100000 \le C \le 10000) and the final state of some of the lamps after some operations have been executed. Determine all the possible final configurations of the NN lamps that are consistent with the given information, without repetitions.

输入格式

  • Line 1: NN.
  • Line 2: Final value of CC.
  • Line 3: Some lamp numbers ON in the final configuration, separated by one space and terminated by the integer 1-1.
  • Line 4: Some lamp numbers OFF in the final configuration, separated by one space and terminated by the integer 1-1.

No lamp will be listed twice in the input.

输出格式

Lines with all the possible final configurations, without repetitions, of all the lamps. Each line has NN characters, where the first character represents the state of lamp 11 and the last character represents the state of lamp NN. A 0 stands for a lamp that is OFF, and a 1 stands for a lamp that is ON. The lines must be ordered from least to largest as binary numbers.

If there are no possible configurations, output a single line with the single word IMPOSSIBLE.

10
1
-1
7 -1

0000000000
0101010101
0110110110

提示

Sample explanation

Input

In this case, there are 1010 lamps and only one button has been pressed. Lamp 77 is OFF in the final configuration.

Output

In this case, there are three possible final configurations:

  • All lamps are OFF.
  • Lamps 1,3,5,7,91,3,5,7,9 are OFF and lamps 2,4,6,8,102,4,6,8,10 are ON.
  • Lamps 1,4,7,101,4,7,10 are OFF and lamps 2,3,5,6,8,92,3,5,6,8,9 are ON.

USACO Training Section 2.2.