`answer = f("?","?","?","?","?")`

?

 

 

 

Instructions

Think of a number from 1 to 31.  And then answer the questions:

• Is your number in GRID 'A'?
• Is your number in GRID 'B'?
• Is your number in GRID 'C'?
• Is your number in GRID 'D'?
• Is your number in GRID 'E'?

And vCalc will magically (i.e. mathematically) tell you the number.

Thanks to Chuck Trautwein for this fun little exercise in binary numbers.

The Math / Science

While it may seem like Mind Reading or Magic, it's just math, specifically binary math. If you have, five yes/no bits represented as zeroes and ones, you can use those bits to specify a base 10 number (what we use every day) from 1 to 31.  Look at the list below.  Do you see patterns?  This is exactly how a computer represents numbers.  The cards above each list the numbers that have the bits 1 through five listed.

1. 0,0,0,0,1
2. 0,0,0,1,0
3. 0,0,0,1,1
4. 0,0,1,0,0
5. 0,0,1,0,1
6. 0,0,1,1,0
7. 0,0,1,1,1
8. 0,1,0,0,0
9. 0,1,0,0,1
10. 0,1,0,1,0
11. 0,1,0,1,1
12. 0,1,1,0,0
13. 0,1,1,0,1
14. 0,1,1,1,0
15. 0,1,1,1,1
16. 1,0,0,0,0
17. 1,0,0,0,1
18. 1,0,0,1,0
19. 1,0,0,1,1
20. 1,0,1,0,0
21. 1,0,1,0,1
22. 1,0,1,1,0
23. 1,0,1,1,1
24. 1,1,0,0,0
25. 1,1,0,0,1
26. 1,1,0,1,0
27. 1,1,0,1,1
28. 1,1,1,0,0
29. 1,1,1,0,1
30. 1,1,1,1,0
31. 1,1,1,1,1

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Computer Science Calculators

• Convert Integer to Binary
• Convert Binary to Integer
• Convert Integer to Octal
• Convert Integer to Hex
• Convert Binary to Hex
• Convert Binary to Octal
• Convert Hex to Decimal
• Convert Hex to Octal
• Convert Octal to Decimal
• Convert Octal to Binary
• Convert Octal to Hex
• Pick a Number between 1 and 31 (binary game)
• Character to Unicode
• Binary Math
• Octal Math
• Hex Math
• Cyclomatic Complexity

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String Manipulation Utilities

• String Compare: Examines two given strings to see if they are equal to each other.
• Palindrome Check: Evaluates if a given word or sentence is a palindrome. 
• Reverse String: Takes a given string of alphanumeric characters and reverses its order.
• Remove Vowels Consonants Numbers Whitespace: Removes all vowels, consonants, numbers, or whitespace from a string of text.
• String to Comma-Separated List: Takes any string and split it into a comma-separated list with options for spaces, bracket types, and capital letters. 
• Word Count: Counts the number of words in a given string regardless of punctuation and new lines. 
• Character Count: Counts the number of occurrences of each character in a string of text.
• Regex Remove: Takes a regex expression and compares it to a sample string to see which patterns should be removed from the string.
• Affine Cipher Encrypt: Encrypts ciphertext using an Affine Cipher algorithm given the ciphertext and two keys.
• Affine Cipher Decrypt: Decrypts ciphertext using an Affine Cipher algorithm given the ciphertext and two keys.
• Caesar Cipher Encrypt: Encrypts non-numeric data by shifting the letters forward or backward on the alphabet by a constant amount. 
• Caesar Cipher Decrypt: Dencrypts non-numeric data by shifting the letters forward or backward on the alphabet by a constant amount.
• String Alphabet Position Sum: Takes a string and converts each character to an integer corresponding to its position in the alphabet and then sums those positions.