Algorithms and Data Structures

• Status
• 1
Implementation
• 2
Bitwise operations
• 3
Prefix Sums
• 4
Sliding window / Two pointers
• 5
Modular Arithmetic
• 6
Number Theory
• 7
Binary Search
• 8
Basic Sorting
• 9
Greedy Algorithms

• # Sudoku

Given a sudoku grid, you are asked if itβs a valid one.
A valid sudoku grid should have:
• All the numbers from 1 to 9 on each row.
• All the numbers from 1 to 9 on each column.
• All the numbers from 1 to 9 inside the cells.
So, the invalid sudoku grid might have:
• Some repeating numbers on some rows
• Some repeating numbers on some columns
• Some repeating numbers inside the cells.

#### Input

The input contains a grid of numbers. All the filled numbers are integers from 0 to 9. The empty cells are represented as 0s.

#### Output

The program should print Valid in case the grid is valid and Not valid otherwise.

#### Examples

 Input Output 0 0 0 0 0 8 0 0 2 0 7 0 0 0 0 0 1 0 0 2 0 7 0 0 9 0 0 0 0 0 0 0 0 7 0 1 0 0 0 9 0 2 6 0 0 3 0 5 8 0 0 0 4 0 9 0 0 6 0 0 4 0 0 0 0 0 2 0 7 0 6 0 0 0 1 0 0 4 0 0 0 Valid 0 0 0 0 0 8 0 0 2 0 7 0 0 0 0 0 1 0 0 2 0 7 0 0 9 0 0 0 0 0 0 0 0 7 0 1 0 6 0 9 0 2 6 0 0 3 0 5 8 0 0 0 4 0 9 0 0 6 0 0 4 0 0 0 0 0 2 0 7 0 6 0 0 0 1 0 0 4 0 0 0 Not valid
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