A fast sudoku solver in C++
$ git clone [email protected]:voltrevo/sudokuSolver.git
$ cd sudokuSolver
$ clang++ sudokuSolver.cpp -O3 -std=c++11 -o sudokuSolver
I've included a large collection of 17-clue sudoku puzzles as sudoku17.txt, which can also be found here. Each line of this file describes separate puzzle, with zeros for empty cells and numbers for provided clues. I usually use the head command to pull out individual puzzles:
$ head -n1 sudoku17.txt
000000010400000000020000000000050407008000300001090000300400200050100000000806000
The compiled binary simply reads this format from stdin and writes solutions in this format to stdout:
$ head -n1 sudoku17.txt | ./sudokuSolver
693784512487512936125963874932651487568247391741398625319475268856129743274836159
On my machine (13" Macbook Pro 2014), it solves the first 100 of these puzzles in an average of 3.8 milliseconds each:
$ time head -n100 sudoku17.txt | ./sudokuSolver >/dev/null
real 0m0.379s
user 0m0.371s
sys 0m0.007s