FastPrep
Problem · Intervals

Obstacle Placement Queries

Learn this problem
● MediumTiktokOA
See Tiktok hiring insights

Problem statement

You are given an infinite number line and an array operations. Process the operations in order while maintaining the coordinates that contain obstacles.

  • [1, x]: Place an obstacle at coordinate x. Coordinate x is guaranteed to contain no obstacle when this operation is performed.
  • [2, x, size]: Check whether a block of length size can begin at coordinate x. The block would occupy every integer coordinate from x through x + size - 1. Append '1' to the answer if none of those coordinates contains an obstacle; otherwise append '0'. This operation only checks feasibility and does not place the block.

Return the binary string formed by the results of all type-2 operations in their original order.

Function

obstaclePlacementQueries(operations: int[][]) → String

Examples

Example 1

operations = [[2, 0, 2], [1, 1], [2, 0, 2], [2, 2, 2]]return = "101"
  1. [2, 0, 2] checks coordinates 0 and 1. There are no obstacles, so append 1.
  2. [1, 1] places an obstacle at coordinate 1.
  3. [2, 0, 2] now intersects the obstacle at coordinate 1, so append 0.
  4. [2, 2, 2] checks coordinates 2 and 3. Both are free, so append 1.

More Tiktok problems

drafts saved locally
public String obstaclePlacementQueries(int[][] operations) {
  // write your code here
}
operations[[2, 0, 2], [1, 1], [2, 0, 2], [2, 2, 2]]
expected"101"
checking account