ARC087B
https://gyazo.com/5a94da0c2e1a0f43970c6ca3b1c71e40
Thoughts.
Since the rotation is 90 degrees, the problem can be split into two independent problems in the x-axis and y-axis directions by splitting the problem with a rotation instruction.
divide into X and Y
The part followed by the forward instruction can be replaced by a number.
Given a set of numbers, the problem is to add or subtract them to a desired value.
How do you solve this...
At worst, there are 2000 numbers, there can be 2^2000 different expressions.
When there are many identical numbers, they can be processed together.
Example, when there are 100 1s, the reachable range is an even number from -100 to 100
Official Explanation
You are right to divide it into X and Y.
The range of possible values is 16000 and the number of steps is 2000, so it is possible to DP in time.
The division into X and Y makes N^2 become 2N.
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