# Create 3 integer variables
dog, cat, mouse = Ints('dog cat mouse')
solve(dog >= 1,   # at least one dog
      cat >= 1,   # at least one cat
      mouse >= 1, # at least one mouse
      # we want to buy 100 animals
      dog + cat + mouse == 100,  
      # We have 100 dollars (10000 cents):
      #   dogs cost 15 dollars (1500 cents), 
      #   cats cost 1 dollar (100 cents), and 
      #   mice cost 25 cents 
      1500 * dog + 100 * cat + 25 * mouse == 10000)
