Proof: Byte 2 Stays the Same 22
Let's prove the following theorem:
if the following are true:
    
    - instruction #4 is 
add dst=3 src1=1 src2=2 - the PC at time 22 = 4
 - value of cell 2 at time 22 = 3
 
then value of cell 2 at time 23 = 3
Instructions
        
    | Memory Cells | 
|---|
| Program Counter | Time | 
|---|---|
| 0 | 0 | 
  
  
LW Computer Simulator
Proof:
  
      
      Given
      
    
    
      
  
  
| 1 | instruction #4 is add dst=3 src1=1 src2=2 | 
      
|---|---|
| 2 | the PC at time 22 = 4 | 
| 3 | value of cell 2 at time 22 = 3 | 
| # | Claim | Reason | 
|---|---|---|
| 1 | not (2 = 3) | not (2 = 3) | 
| 2 | value of cell 2 at time (22 + 1) = value of cell 2 at time 22 | if instruction #4 is add dst=3 src1=1 src2=2 and the PC at time 22 = 4 and not (2 = 3), then value of cell 2 at time (22 + 1) = value of cell 2 at time 22  | 
  
| 3 | 22 + 1 = 23 | 22 + 1 = 23 | 
| 4 | value of cell 2 at time (22 + 1) = value of cell 2 at time 23 | if 22 + 1 = 23, then value of cell 2 at time (22 + 1) = value of cell 2 at time 23 | 
| 5 | value of cell 2 at time 23 = value of cell 2 at time 22 | if value of cell 2 at time (22 + 1) = value of cell 2 at time 23 and value of cell 2 at time (22 + 1) = value of cell 2 at time 22, then value of cell 2 at time 23 = value of cell 2 at time 22 | 
| 6 | value of cell 2 at time 23 = 3 | if value of cell 2 at time 23 = value of cell 2 at time 22 and value of cell 2 at time 22 = 3, then value of cell 2 at time 23 = 3 | 
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