Work continues on the remote control car project. Bandwidth in the telemetry system is at a premium and you have been asked to implement a message protocol for communicating telemetry data.
Data is transmitted in a buffer (byte array). When integers are sent, the size of the buffer is reduced by employing the protocol described below.
Each value should be represented in the smallest possible integral type (types of byte and sbyte are not included as the saving would be trivial):
| Min Value | Max Value | Type |
|---|---|---|
| 4,294,967,296 | 9,223,372,036,854,775,807 | long |
| -9,223,372,036,854,775,808 | -2,147,483,649 | long |
| 2,147,483,648 | 4,294,967,295 | uint |
| 65,536 | 2,147,483,647 | int |
| -2,147,483,648 | -32,769 | int |
| 0 | 65,535 | ushort |
| -32,768 | -1 | short |
The value should be converted to the appropriate number of bytes for its assigned type. The complete buffer comprises a byte indicating the number of additional bytes in the buffer (prefix byte) followed by the bytes holding the integer (payload bytes).
If the payload bytes represent a signed type (short, int or long) then the prefix byte should contain the length as a negative number.
Only the prefix byte and the number of following bytes indicated by the prefix will be sent in the communication. Internally a 9 byte buffer is used (with trailing zeroes, as necessary) both by sending and receiving routines.
Please implement the static method TelemetryBuffer.ToBuffer() to encode a buffer taking the parameter passed to the method.
TelemetryBuffer.ToBuffer(5)
// => {0x2, 0x5, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
TelemetryBuffer.ToBuffer(Int32.MaxValue)
// => {0xfc, 0xff, 0xff, 0xff, 0x7f, 0x0, 0x0, 0x0, 0x0 };
TelemetryBuffer.ToBuffer(-1)
// => {0xfe, 0xff, 0xff, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };Please implement the static method TelemetryBuffer.FromBuffer() to decode the buffer received and return the value in the form of a long.
TelemetryBuffer.FromBuffer(new byte[] {0xfc, 0xff, 0xff, 0xff, 0x7f, 0x0, 0x0, 0x0, 0x0 })
// => 2147483647If the prefix byte is not one of -8, -4, -2, 2, 4 then 0 should be returned.