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Dry-running nested while loops using a trace table - Answers

Dry-run this code using the table provided. When you have worked through the code, run the code in Python and compare the output you get to what you predicted on paper. Remember, only change a value if it changes, and move on to the next line after each change. The table has been started for you. (Note: len(monsters) = 3)

1    monsters=["Ghost","Warlock","Dragon"]
2    tries=0
3    manuscript=""
4    while tries < len(monsters) :
5         count=0
6         while count<tries :
7              print(count<tries)
8              manuscript += monsters[count]
9              manuscript += " and "
10            count+=1
11       manuscript += monsters[tries]
12       manuscript += ". "
13       if tries == len(monsters) - 1 :
14            manuscript += " We will fight them and win ..."
15       tries +=1
16   print (manuscript)

line tries manuscript tries < 3 count count<tries tries==len(monsters)-1 output
2 0            
3   ''          
4     True        
5       0      
6         0 < 0 = False    
11   Ghost          
12   Ghost.          
13           0 == 2 is False  
15 1            
6         0 < 1 = True     
 7             True 
 8   'Ghost. Ghost'          
 9   'Ghost. Ghost and'           
 10        1      
6         1 < 1 = False     
11   Ghost. Ghost and Warlock          
12   Ghost. Ghost and Warlock.
          
13            1 == 2 is False  
15 2             
4      True        
5        0      
6         0 < 2 = True    
 7             True 
 8   Ghost. Ghost and Warlock. Ghost and          
 9              
10       1      
6         1 < 2 = True    
7             True
8   Ghost. Ghost and Warlock. Ghost and Warlock          
9   Ghost. Ghost and Warlock. Ghost and Warlock and          
10       2      
6         2 < 2 = False    
11   Ghost. Ghost and Warlock. Ghost and Warlock and Dragon          
12   Ghost. Ghost and Warlock. Ghost and Warlock and Dragon.          
13           2 == 2 is True  
14   Ghost etc We will fight them and win ...          
15 3            
4     False        
 16             Ghost etc We will fight them ...

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