Solution: Self Crossing
Explore how to determine if a path defined by sequential movements on an X-Y plane crosses itself. Learn to apply mathematical and geometric conditions to identify self crossings without tracking coordinates. Understand three primary intersection cases and implement an efficient O(n) time solution to solve this common coding interview pattern.
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Statement
You are given an array of integers, distance, where each element represents the length of a move you will make on an X-Y plane. You start at the origin, which is point distance[0] meters north, distance[1] meters west, distance[2] meters south, distance[3] meters east, and continue this pattern in a counterclockwise direction. Each step follows the sequence—north, west, south, east—repeating as long as there are remaining distances in the array.
Your task is to determine whether this path crosses itself at any point. This means checking whether you revisit any previously visited position (including the origin or any other point) at any step. Return TRUE if the path intersects itself, and FALSE otherwise.
Constraints:
1
distance.length...