Asana Interview Questions (2026-2027)

Round 1 Coding / OOD

Problem

Design an ASCII art rendering system. Support rendering rectangles, triangles, and text banners to a 2D character canvas. Each shape is a separate class. The canvas can combine multiple shapes and print the result.

python
class Canvas:
    def __init__(self, width: int, height: int, fill: str = " "):
        ...
    def draw(self, shape: 'Shape', x: int, y: int) -> None:
        ...
    def render(self) -> str:
        ...

class Rectangle:
    def __init__(self, width: int, height: int, char: str = "*"):
        def pixels(self) -> list[tuple[int,int]]: ...

class TextBanner:
    def __init__(self, text: str):
        def pixels(self) -> list[tuple[int,int,str]]: ...

Example

c = Canvas(10, 5)
c.draw(Rectangle(4, 3, "#"), x=1, y=1)
c.render()
# ----------
# |        |
# | ####   |
# | ####   |
# | ####   |
# ----------

Follow-ups

1. How do you handle overlapping shapes — which one takes priority and why?
2. How would you add a Triangle shape that fills using Bresenham's line algorithm?
3. How would you support layering (z-index) so shapes can be explicitly ordered?
4. How would you serialize the canvas state to a JSON file and restore it?