#2075

Decode the Slanted Ciphertext

specialist · 885 · lc medium +31 · verified · 50.3% accepted · 269 likes · top 38%

Description

A slanted transposition cipher encodes originalText by writing it diagonally (top-left to bottom-right) into a matrix with rows rows, padding empty cells with spaces, then reading the matrix row-by-row to form encodedText. Given encodedText and rows, decode and return originalText (which has no trailing spaces). The answer is guaranteed to be unique.

Example 1:

Input: encodedText = "ch ie pr", rows = 3

Output: "cipher"

Explanation: This is the same example described in the problem description.

Example 2:

Input: encodedText = "iveo eed l te olc", rows = 4

Output: "i love leetcode"

Explanation: The figure above denotes the matrix that was used to encode originalText.

The blue arrows show how we can find originalText from encodedText.

Example 3:

Input: encodedText = "coding", rows = 1

Output: "coding"

Explanation: Since there is only 1 row, both originalText and encodedText are the same.

Code

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class Solution:
    def decodeCiphertext(self, encodedText: str, rows: int) -> str:

class Solution:
    def decodeCiphertext(self, encodedText: str, rows: int) -> str: