Robot Back on Old Ground

Easy

A robot vacuum starts at (0, 0) on a grid floor and follows route, a string of commands. Each command moves it one cell: 'N' north, 'S' south, 'E' east, 'W' west. Return True if at some moment the robot stands on a cell it has already visited (the starting cell counts), and False if every cell on the route is new.

Example 1

route="NNEESW" → False

The robot visits (0,1), (0,2), (1,2), (2,2), (2,1), (1,1) — all different.

Example 2

route="ENWS" → True

Four steps around a square bring the robot back to its start (0,0).

Example 3

route="WE" → True

Constraints

1 ≤ len(route) ≤ 10⁵
route contains only 'N', 'S', 'E' and 'W'

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Hash Table String

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Input

route="NNEESW"

Expected

False

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