Shifting byte and remaining values

Projects Programming
1

Can someone explain way the code that you see below give these results?

void loop() {

	byte test=00000101;
	Serial.print("the byte test is:");
	Serial.println(test);
	int x=(int)test;
	int y=(int)test<<8;
	Serial.print("the int x is:");
	Serial.println(x);
	Serial.print("the int shifted y is:");
	Serial.println(y);

	byte tost=10000001;
	int z=test+tost;
	Serial.print("the int z is:");
	Serial.println(z);

	delay(1000);

}

Results:

the byte test is:65
the int x is:65
the int shifted y is:16640
the int z is:194

While if i change the test to 00000001 it performs great:

changed code:

void loop() {

	byte test=00000001;
	Serial.print("the byte test is:");
	Serial.println(test);
	int x=(int)test;
	int y=(int)test<<8;
	Serial.print("the int x is:");
	Serial.println(x);
	Serial.print("the int shifted y is:");
	Serial.println(y);

	byte tost=10000001;
	int z=test+tost;
	Serial.print("the int z is:");
	Serial.println(z);

	delay(1000);

}

the byte test is:1
the int x is:1
the int shifted y is:256
the int z is:130

2

Can someone explain way the code that you see below give these results?

What part don't you understand?

	byte test=00000101;

Any literal starting with a 0 is interpreted as an octal value, not binary or decimal or hexadecimal.