1. Hw 5 Hints

2. Managing Complexity Many different ways to solve this problem
Write and test one function at a time
Try to use a statically allocated array with say, 100 char
Convert to a dynamically allocated array later
Creating little helper functions
Reverse string
Multiply up to 10
Max, min

3. Debugging Remember to check operands of different lengths
Use a global debugging counter to track memory allocation
Update the counter whenever new and delete are called

4. The Least Significant Digit First
Integer to string
Addition

5. Integer to String 123 -> “123” 123 % 10 = 3, ‘3’ = 3 + ‘0’
123 / 10 = 12
12 % 10 = 2, ‘2’ = 2 + ‘0’
12 / 10 = 1
1 % 10 = 1, ‘1’ = 1 + ‘0’
1 / 10 = 0 // terminate

6. Addition

7. The Most Significant Digit First
Multiplication
Comparison of two numbers of the same length

8. Multiplication
1111 X

9. Same as… 1111 X 111 ------------ + 1111 ------------- 12321

10. Same as…
1111 x 111
= ((1 x 1111) x x 1111) x x 1111

11. Comparison If two numbers have the same length
The most significant digit decides which number is bigger
If they are the same, compare the next digit

12. Some Possible Ways to Store 123
“123”
Easier to print and extract input
Easier to write the string conversion constructor
Easier to multiply
Easier to compare numbers
“321”
Easier to write the integer conversion constructor
Easier to add two numbers
Lowest significant digit first