func main() {
numSolutions = 0
// create the grid.
grid := *datatypes.InitGrid()
count := 0
inputValues := make(map[int]bool)
// read input into the grid.
for i := 0; i < max; i++ {
count += readRow(&grid, i, inputValues)
}
// At least 17 values, and 8 distinct values are required for a unique solution. (Necessary condition, but not sufficient).
if count < 17 || len(inputValues) < 8 {
handleError("Too few input values given. At least 17 values, and 8 distinct values must be given.", nil)
}
// solve using given inputs without making any guess.
positions := solve(&grid, count)
// make a guess for a position and start solving; backtrack if there is any conflict.
solveByGuessing(&grid, positions, 0)
fmt.Println("Total solutions:", numSolutions)
// Set difficulty as easy if solved without making any guess, medium if number of guesses is less than 9, and hard otherwise.
difficultyLevel := easy
if len(positions) > 0 {
if len(positions) < max {
difficultyLevel = medium
} else {
difficultyLevel = hard
}
}
fmt.Println("Difficulty level:", difficultyLevel)
}
// TestSolve initializes and solves the grid.
func TestSolve(t *testing.T) {
grid := *datatypes.InitGrid()
count := setInput(&grid)
positions := solve(&grid, count)
if len(positions) < 37 {
t.Error("Expected at least 37, got ", len(positions))
}
solveByGuessing(&grid, positions, 0)
}
func BenchmarkSolve(b *testing.B) {
for n := 0; n < b.N; n++ {
grid := *datatypes.InitGrid()
count := setInput(&grid)
positions := solve(&grid, count)
if len(positions) != 37 {
b.Error("Expected 37, got ", len(positions))
}
solveByGuessing(&grid, positions, 0)
}
}