#777

Swap Adjacent in LR String

expert · 1090 · lc medium +32 · verified · 37.9% accepted · 1,334 likes · top 16%

⚑ Converging Pointers (Pair / Triple Sum)

Description

In a string of 'L', 'R', and 'X' characters, 'L' can slide left over 'X' (replacing "XL" with "LX") and 'R' can slide right over 'X' (replacing "RX" with "XR"). Neither 'L' nor 'R' can pass through each other.

Given strings start and result, return True if start can be transformed into result by any sequence of such moves.

Example 1:

Input: start = "RXXLRXRXL", result = "XRLXXRRLX"

Output: true

Explanation: We can transform start to result following these steps:

RXXLRXRXL ->

XRXLRXRXL ->

XRLXRXRXL ->

XRLXXRRXL ->

XRLXXRRLX

Example 2:

Input: start = "X", result = "L"

Output: false

Code

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class Solution:
    def canTransform(self, start: str, result: str) -> bool:

class Solution:
    def canTransform(self, start: str, result: str) -> bool: