One simple way to resolve collisions in an array implementation is to use linear probing. That is, just try the next position:

        hash(14913) = 14913 % 7 = 3
        hash(15930) = 15930 % 7 = 5
        hash(16918) = 16918 % 7 = 6
        hash(17020) = 17020 % 7 = 3
        -----------
        0 null
        1 null
        2 null
        3 (14913, 20) (17020, 19) goes in next available spot
        4 (17020, 19)
        5 (15930, 10)
        6 (16918, 50)


        How many comparisons must be made now, to look up key 14913?
        What about key 17020?
        Where would (14920, 40) go? hash(14920) = 14920 % 7 = 3
        Answer: Position 0; that is, next available just wraps around to the
        beginning of the array if necessary.