Difference between revisions of "CSC103: DT's Notes 1"
Line 208: | Line 208: | ||
− | + | 1 3 3 | |
+ 3 8 5 | + 3 8 5 | ||
− | ------------ | + | ------------ |
− | |||
It's tempting to just go ahead and find the answer, isn't it? Instead let's do it a different way and concentrate only on 3 + 5 | It's tempting to just go ahead and find the answer, isn't it? Instead let's do it a different way and concentrate only on 3 + 5 | ||
Line 218: | Line 217: | ||
1 | 1 | ||
2 | 2 | ||
− | 3 <---- we start at 3 | + | <font color="magenta">3</font <---- we start at 3 |
4 +1 | 4 +1 | ||
5 +2 | 5 +2 | ||
6 +3 | 6 +3 | ||
7 +4 | 7 +4 | ||
− | 8 +5 and we go down by 5 steps. | + | <font color="magenta">8</font> +5 and we go down by 5 steps. |
9 | 9 | ||
The result is 8. | The result is 8. | ||
− | + | 1 3 3 | |
+ 3 8 5 | + 3 8 5 | ||
------------ | ------------ | ||
− | + | <font color="magenta">8</font> | |
We move on the next column and add 3 + 8. | We move on the next column and add 3 + 8. | ||
Line 238: | Line 237: | ||
1 | 1 | ||
2 | 2 | ||
− | 3 <---- we start at 3 | + | <font color="magenta">3</font> <---- we start at 3 |
4 +1 | 4 +1 | ||
5 +2 | 5 +2 | ||
Line 247: | Line 246: | ||
----- | ----- | ||
1 0 +7 | 1 0 +7 | ||
− | 1 1 +8 <--- the result is 8, but with a roll-over | + | <font color="green">1</font> <font color="magenta">1</font> +8 <--- the result is 8, but with a roll-over |
+ | |||
+ | |||
+ | Here we had to roll over our list of available digits. We know the rule! When we roll over we add 1 to the digit on the left. In this case the digit'''s''' on the left. We'll put this new digit (green) above the third column of numbers as follows: | ||
+ | |||
+ | <font color="green">1</font> | ||
+ | 1 3 3 | ||
+ | + 3 8 5 | ||
+ | ------------ | ||
+ | <font color="magenta">1</font> 8 | ||
+ | |||
+ | So now we have 3 numbers to add: 1, 1 and 3: | ||
+ | |||
+ | 0 | ||
+ | <font color="magenta">1</font> <---- we start at 1 | ||
+ | 2 +1 | ||
+ | 3 +and we start again adding 3: +1 | ||
+ | 4 +2 | ||
+ | <font color="magenta">5</font> +3 | ||
+ | 6 | ||
+ | 7 | ||
+ | 8 | ||
+ | 9 | ||
+ | The result: | ||
− | + | 1 3 3 | |
− | |||
− | |||
+ 3 8 5 | + 3 8 5 | ||
------------ | ------------ | ||
− | + | <font color="magenta">5</font> 1 8 | |
+ | |||
+ | |||
+ | |||
+ | |||
+ | |||
+ | |||
The answers to these questions, and the ensuing solutions are provided by two giants of computer science, '''George Boole''', and '''Claude Shannon''' who worked at very different times. | The answers to these questions, and the ensuing solutions are provided by two giants of computer science, '''George Boole''', and '''Claude Shannon''' who worked at very different times. |
Revision as of 11:01, 31 January 2012
--© D. Thiebaut 08:10, 30 January 2012 (EST)