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LeetCode solutions

1119. Robot Bounded In Circle

My accepted Python solution to LeetCode problem 1119, Robot Bounded In Circle, running in 0ms.

  • Difficulty: Medium
  • Python
  • Runtime 0ms
  • Memory 17.5MB

Read the problem on LeetCode View on GitHub

The problem statement is LeetCode’s and stays on their site. What follows is my accepted solution.

Python

Accepted on LeetCode — runtime 0ms, memory 17.5MB, accepted 2026-01-02.

python
class Solution:
    def isRobotBounded(self, instructions: str) -> bool:
        # Direction vectors: North, East, South, West
        directions = [(0, 1), (1, 0), (0, -1), (-1, 0)]
        dir_idx = 0  # Start facing North
        x, y = 0, 0
        
        for c in instructions:
            if c == 'G':
                x += directions[dir_idx][0]
                y += directions[dir_idx][1]
            elif c == 'L':
                dir_idx = (dir_idx - 1) % 4
            else:  # R
                dir_idx = (dir_idx + 1) % 4
        
        # Bounded if: back at origin OR not facing North
        return (x == 0 and y == 0) or dir_idx != 0

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