Introduction. Practice Task 1

1. Compute Hamming Distance

The Hamming distance between two strings of equal length is the number of positions at which the corresponding symbols are different.

For example:

                        karolin         1011101         2173896
                        kathrin         1001001         2233796
                          ^^^             ^ ^            ^^ ^
Hamming Distance:          3               2               3

Implementation notes

If strings length is not equal - return -1.

2. Answer Bob

Bob is quite strange teenager and his responses are very (very!) limited:

• Bob answers 'Yeap.' if you ask him a question.
• He answers 'Chill out!' if you yell at him.
• He says 'Fine.' if you address him without actually saying anything.
• He answers 'Whatever.' to anything else.

3. Console calculator

Create console calculator, that implements following operations:

• addition
• subtraction
• multiplication
• division
• exit
• help

Addition

Should be called with add keyword. After command is entered 2 numbers should be entered by user, separated with newline symbol(\n). After command execution result of command execution should be printed to System.out and should contain both operands, operation and execution result: 1+2 3

Subtraction

Should be called with sub keyword. After command is entered 2 numbers should be entered by user, separated with newline symbol(\n). After command execution result of command execution should be printed to System.out and should contain both operands, operation and execution result: 1-2 -1

Multiplication

Should be called with mul keyword. After command is entered 2 numbers should be entered by user, separated with newline symbol(\n). After command execution result of command execution should be printed to System.out and should contain both operands, operation and execution result: 2*2 4

Division

Should be called with div keyword. After command is entered 2 numbers should be entered by user, separated with newline symbol(\n). After command execution result of command execution should be printed to System.out and should contain both operands, operation and execution result: 2/2 1

Exit

should be called with exit keyword. Should print Bye-bye before exiting the program.

Help

Help message should be printed to System.out and user should be requested to make new choice.

Possible inputs and outputs of program.

>> Console calculator:
>> Enter 'add' to perform addition.
>> Enter 'sub' to perform subtraction.
>> Enter 'mul' to perform multiplication.
>> Enter 'div' to perform division.
>> Enter 'exit' to exit.
>> Enter 'help' to see help message.
>> Make your choice.
<< add
>> Enter first number:
<< 1
>> Enter second number:
<< 2
>> Result of 1+2 is 3
>> Make your choice.
<< exit
>> Bye-bye.