def solve(data):
SOLUTION = ' ' * 81
solver = BacktrackingSolver()
# data = "XX3X2X6XX9XX3X5XX1XX18X64XXXX81X29XX7XXXXXXX8XX67X82XXXX26X95XX8XX2X3XX9XX5X1X3XX"
layer = Layer(data, SOLUTION)
sol = solver.solve(layer)
d = list(data)
for s in sol:
d[s[0]] = s[1]
return int("".join(d[:3]))
