SudokuHard

Hard Sudoku — Puzzle 267

876
5963
49
2491
5486
71
182
31
85

How to play

Fill every row, every column and every 3 by 3 box with the numbers 1 to 9, using each number once.

This puzzle has 26 given numbers and exactly one solution, so it can always be finished by reasoning alone.

821739645
597468123
463521978
284916357
935247816
716853492
179385264
352694781
648172539