CSCI 101: Intro to Computer Science

Assignment 5.     Due: Mon, Jul 7

Solutions will be posted on Wed, Jul 9

Please save your work in a single text file hw5.txt and upload it on Canvas before midnight of the day above.

1. (3x5=15 points)   Convert the following binary numbers to decimal:
   1. 1111
   2. 101001
   3. 110011

2. (3x5=15 points)   Convert the following decimal numbers to binary:
   1. 45
   2. 258
   3. 1111

3. (2x5=10 points)  
   1. Convert the following HEX number to decimal: CAB
   2. Write your first name in ASCII code.

4. (2x10=20 points)   Write PIPPIN programs to perform the following tasks:
   1. Swap the contents of cells 5 and 6
   2. Compute the absolute value |X| of a number stored in a cell X. The absolute value is defined as follows:

      if X > 0, then |X| = X
      if X < 0, then |X| = -X
      

      For example, 5 > 0, so |5| = 5.
      On the other hand, -3 < 0, so |-3| = -(-3) = +3.

5. (20 points)   Write a PIPPIN program to compute X=(A+B)*(C+D), assuming A,B,C,D, and X are stored in cells 100, 101, 102, 103, and 104 respectively.

6. (2x10=20 points)   Draw the parse trees for the following algebraic expressions:
   1. ((x + y) + z) * (x + z)
   2. 1 + (2*(1 + 2*(1 + x)))
   You can use Paint to draw the parse trees, or just type them in the text mode. For example, following the second approach a parse tree for the expression (a + b) * c should look like this:

           a   b 
            \ /
             +   c
              \ /
               *