http://www.cs.cmu.edu/afs/cs.cmu.edu/academic/class/15251-s05/Site/Materials/Directions/circuits/
# 2-input XOR gate
# 2-input NOR gate
# 2-input OR gate
# 2-input NAND gate
# 2-input AND gate
# Inverter
이런 것이 들어있음.
# 2-input XOR gate
# 2-input NOR gate
# 2-input OR gate
# 2-input NAND gate
# 2-input AND gate
# Inverter
이런 것이 들어있음.