A961.Spaceship--Platinum

NOI/NOI+/CTSC

USACO

通过率:0%

时间限制:1.00s

内存限制:128MB

题目描述

Bessie the cow has been abducted by aliens and is now trapped inside an alien
spaceship! The spaceship has NN (1N60)(1\le N\le 60) rooms labeled 1N1\ldots N,
with one-way doors connecting between some pairs of rooms (due to the strange
alien technology at play, it is even possible for a door to lead from a room
back to itself!). However, no two doors share the same starting and end room.
Additionally, Bessie has a remote with buttons numbered 1K1\ldots K (1K60)(1 \le K \le 60).
The aliens will release Bessie if she can complete a strange task. First, they
will choose two rooms, ss and tt (1s,tN)(1 \le s, t \le N), and two numbers,
bsb_s and btb_t (1bs,btK)(1 \le b_s, b_t \le K). They will start Bessie in room ss
and immediately have her press button bsb_s. Bessie will then proceed to
navigate the ship while pressing buttons. There are a few rules for what
Bessie can do:

  • In each room, after pressing exactly one button, she must choose to either exit through a door to another (possibly the same) room or stop.
  • Once Bessie presses a button, it is invalid for her to press the same button again unless, in the time between uses, she has pressed a button with a higher number. In other words, pressing button number xx will make it unavailable for use, while all buttons with numbers <x<x will be reset and again available for use.
  • If Bessie presses an invalid button, she automatically fails and the aliens will keep her.
    Bessie is released only if she stops in room tt, the last button she pressed
    was btb_t, and no invalid buttons were ever pressed.
    Bessie is worried that she may not be able to complete the task. For QQ
    (1Q60)(1\le Q\le 60) queries, each consisting of what Bessie considers a likely
    choice of s,t,bss, t, b_s, and btb_t, Bessie wants to know the number of sequences
    of rooms and button presses that would lead to her release. Report your
    answers modulo 109+710^9 + 7 as they may be very large.

输入格式

The first line contains N,K,QN,K,Q.
The next NN lines each contain NN bits (each 0 or 1). The jj-th entry of
the ii-th line is 1 if there exists a door from room ii to room jj, and 0
if no such door exists.
This is followed by QQ lines, each containing four integers bsb_s, ss,
btb_t, tt, denoting the starting button, starting room, final button, and
final room respectively.

输出格式

The number of sequences for each of the QQ queries modulo 109+710^9+7 on
separate lines.

输入输出样例

  • 输入#1

    6 3 8
    010000
    001000
    000100
    000010
    000000
    000001
    1 1 1 1
    3 3 1 1
    1 1 3 3
    1 1 1 5
    2 1 1 5
    1 1 2 5
    3 1 3 5
    2 6 2 6
    

    输出#1

    1
    0
    1
    3
    2
    2
    0
    5
    

说明/提示

The doors connect rooms 121\to 2, 232 \to 3, 343\to 4, 454\to 5, and 666\to 6.
For the first query, Bessie must stop immediately after pressing the first
button.
For the second query, the answer is clearly zero because there is no way to
get to room 1 from room 3.
For the third query, Bessie's only option is to move from room 1 to room 2 to
room 3 while pressing buttons 1, 2, and 3.
For the fourth query, Bessie's pattern of movement is fixed, and she has three
possible sequences of button presses:

  • (1,2,3,2,1)(1,2,3,2,1)
  • (1,2,1,3,1)(1,2,1,3,1)
  • (1,3,1,2,1)(1,3,1,2,1)
    For the last query, Bessie has five possible sequences of button presses:
  • (2)(2)
  • (2,3,2)(2,3,2)
  • (2,3,1,2)(2,3,1,2)
  • (2,1,3,2)(2,1,3,2)
  • (2,1,3,1,2)(2,1,3,1,2)
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