PHP中“+”，“ - ”和“^”运算符之间的区别？

Question

Difference between “+”, “-” and “^” operators in PHP?

echo "<br>";
echo 200+233; //433
echo "<br>";
echo 200^233; //33
echo "<br>";
echo 233^20; //253

As you see sometimes '^' works as '-' and sometimes as '+'...

What a rule?

Answer 1

This is the XOR operator. It's a binary operator that returns true if both inputs are not the same:

0 ^ 0 = 0
0 ^ 1 = 1
1 ^ 0 = 1
1 ^ 1 = 0

So it's looking at the two numbers you have input as binary numbers and comparing each bit and returning a new result:

200 in binary = 11001000
233 in binary = 11101001
result          00100001

That result as a decimal number is 33.