def test_combination_with_duplicate_backtrack(self):
c = Combinations()
input = ['1', '1', '1', '4']
k = 2
res = c.combinations_with_duplicates_backtrack(input, k)
print res
def test_combination_with_duplicate_backtrack(self):
c = Combinations()
input = ['1', '1', '1', '4']
k = 2
res = c.combinations_with_duplicates_backtrack(input, k)
print res
