module sparseMemory();

    typedef enum {false, true} boolean;
    bit[31:0] highestIndex;
    bit[31:0] lowestIndex;
    boolean bigMemory[bit[31:0]];

    initial begin
        for(int i = 0; i < 25; i++) begin
            bigMemory[$urandom] = true;
        end

        bigMemory.first(lowestIndex);
        bigMemory.last(highestIndex);

        $display("bigMemory has %0d inputs", bigMemory.size());
        $display("The lowest index is %0d", lowestIndex);
        $display("The highest index is %0d", highestIndex);
        $display("Here are the addresses");
        foreach(bigMemory[i])
            $display(i);
    end

endmodule