Markov takes out his Snakes and Ladders game, stares at the board and wonders: "If I can always roll the die to whatever number I want, what would be the least number of rolls to reach the destination?"
Rules The game is played with a cubic die of faces numbered to .
Starting from square , land on square with the exact roll of the die. If moving the number rolled would place the player beyond square , no move is made.
If a player lands at the base of a ladder, the player must climb the ladder. Ladders go up only.
If a player lands at the mouth of a snake, the player must go down the snake and come out through the tail. Snakes go down only.
Function Description
Complete the quickestWayUp function in the editor below. It should return an integer that represents the minimum number of moves required.
quickestWayUp has the following parameter(s):
- ladders: a 2D integer array where each contains the start and end cell numbers of a ladder
- snakes: a 2D integer array where each contains the start and end cell numbers of a snake
Input Format
The first line contains the number of tests, .
For each testcase:
- The first line contains , the number of ladders.
- Each of the next lines contains two space-separated integers, the start and end of a ladder.
- The next line contains the integer , the number of snakes.
- Each of the next lines contains two space-separated integers, the start and end of a snake.
Constraints
The board is always with squares numbered to .
Neither square nor square will be the starting point of a ladder or snake.
A square will have at most one endpoint from either a snake or a ladder.
Output Format
For each of the t test cases, print the least number of rolls to move from start to finish on a separate line. If there is no solution, print -1.
Sample Input
2
3
32 62
42 68
12 98
7
95 13
97 25
93 37
79 27
75 19
49 47
67 17
4
8 52
6 80
26 42
2 72
9
51 19
39 11
37 29
81 3
59 5
79 23
53 7
43 33
77 21
Sample Output
3
5
Explanation
For the first test:
The player can roll a and a to land at square . There is a ladder to square . A roll of ends the traverse in rolls.
For the second test:
The player first rolls and climbs the ladder to square . Three rolls of get to square . A final roll of lands on the target square in total rolls.