# Add two numbers, according the the Boolos, et al., conventions.  

# Erase a one and move to the right (state 0).  If the first square is
# blank, move to the right and halt (state 1).  Else, keep moving to
# the right until you find a blank (state 2).  Write 1 there (state
# 2), move to the left until you find a blank (state 3).  When you do,
# move back right (state 3) and erase a 1 and move right again (state
# 4).  Halt.

# St R W M New
0 1 _ r 1   # In state 0, if I see a 1, 
	   # write a blank and move right and goto state 1.
	   # State 0: start state -- erase a one

1 _ _ r 99  # The first number was 0, so I'm okay.
1 1 1 r 2   
           # State 1: 
2 _ 1 l 3   # Put a 1 in the first blank.
2 1 1 r 2 
3 _ _ r 4   # Look for first blank 
3 1 1 l 3 
4 1 _ r 99  # Erase first 1 and halt

4 _ _ r 1000 # Former halt state.
3 1 1 r 1000 # Former halt state.
2 1 1 r 1000 # Former halt state.
99 _ _ r 1000 # Former halt state.
99 1 1 r 1000 # Former halt state.
0 _ _ r 1000 # Former halt state.
# Change 1111 to 4.

100 _ 0 r 200 
100 1 1 r 140 
101 _ * l 104 
102 _ 1 r 103 
103 _ _ r 103 
103 1 _ l 106 
103 * _ l 107 
104 _ 1 r 105 
104 0 1 r 105 
104 1 2 r 105 
104 2 3 r 105 
104 3 4 r 105 
104 4 5 r 105 
104 5 6 r 105 
104 6 7 r 105 
104 7 8 r 105 
104 8 9 r 105 
104 9 0 l 104 
105 * * r 103 
105 0 0 r 105 
105 1 1 r 105 
105 2 2 r 105 
105 3 3 r 105 
105 4 4 r 105 
105 5 5 r 105 
105 6 6 r 105  
105 7 7 r 105 
105 8 8 r 105 
105 9 9 r 105 
106 _ _ l 106 
106 * * l 104 
107 _ _ l 107 
107 * _ l 107 
140 1 1 r 140  #Put an end of string marker
140 _ * l 141 
141 1 1 l 141  #Goto lefthand 1
141 _ _ r 142 
142 1 _ l 101 


1000 _ _ l 100 #Goto start state, machine u2d
1000 1 1 l 100 #Goto start state, machine u2d