How should I practice Layered Rectangle Canvas?

Start by reading the full statement, solve the visible examples, then compare the pattern against related Rippling onsite interview problems in FastPrep.

Is Layered Rectangle Canvas associated with Rippling?

FastPrep tags this as a Rippling onsite interview coding practice problem when the problem catalog has that company and stage context.

Layered Rectangle Canvas

Rippling● MediumFULLTIMEONSITE INTERVIEW

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Problem statement

You are given a rectangular character canvas with rows rows and cols columns. Every uncovered cell initially contains '.'.

Process each string in commands from left to right. Coordinates are zero-indexed, and every command has one of these forms:

DRAW id top left height width ch creates a filled rectangle with a unique identifier id. Its top-left cell is (top, left), it occupies height rows and width columns, and every occupied cell contributes the uppercase character ch. A newly drawn rectangle is placed above every rectangle that already exists.
MOVE id rowDelta colDelta translates the existing rectangle id by adding rowDelta to its top coordinate and colDelta to its left coordinate. Moving a rectangle does not change its layer position.

At any cell covered by multiple rectangles, the topmost rectangle contributes the visible character. When a rectangle moves away, any lower rectangle underneath it becomes visible again.

Return the final canvas as an array of rows strings, each of length cols.

Function

renderRectangleCanvas(rows: int, cols: int, commands: String[]) → String[]

Examples

Example 1

rows = 4cols = 7commands = ["DRAW back 0 0 3 4 A","DRAW front 1 2 2 4 B"]return = ["AAAA...","AABBBB.","AABBBB.","......."]

The rectangle front was drawn later, so its 'B' cells cover the overlapping portion of back.

Example 2

rows = 4cols = 6commands = ["DRAW low 0 0 2 3 L","DRAW high 1 1 2 3 H","MOVE low 1 2"]return = ["......",".HHHL.",".HHHL.","......"]

Moving low preserves its original lower layer. Its cells become visible only where high does not cover them.

Example 3

rows = 5cols = 7commands = ["DRAW base 1 1 3 5 X","DRAW top 2 2 2 2 O","MOVE top -1 3"]return = [".......",".XXXXOO",".XXXXOO",".XXXXX.","......."]

The upper rectangle moves to columns 5 and 6. Its old cells reveal base, while its new overlap at column 5 remains visible as 'O'.

Constraints

1 <= rows, cols <= 50.
1 <= commands.length <= 1000.
At most 200 rectangles are drawn.
Every id is a nonempty alphanumeric string; each DRAW uses a new ID, and each MOVE names an existing ID.
Each ch is one uppercase English letter.
Every rectangle has positive height and width, and every draw or move leaves the complete rectangle inside the canvas.