def csp_sdk(folder, instance):
fo = open("problems/%d/%d.sd"%(folder,instance), "rw+")
sys.setrecursionlimit(1000000)
sudoku = Sudoku()
for line in fo:
l = line.split()
tmp = []
for i in l:
tmp.append(int(i))
if l:
sudoku.add_row(tmp)
fo.close()
starter = sudoku.rst_cst_var()
csp = Solver(sudoku, starter)
result = csp.game()
for l in result.sudoku:
print l
del sudoku
print("\n")
return csp.steps
