That thing below the DIP switch is 4-way pullup resistor network, something like 4x4.7kΩ or 4x10kΩ .. see picture below ..
It ensures that the input is held "H" if switch is open ..
One pin is the common that goes to Vcc and the other four pins are the free ends of the four resistors. The DIP switch connects the free ends to ground for a logic zero and leaves them floating for a logic one.