What does |= mean in c++? -

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i trying understand |= in c++, have sample code

 int x = 0 ;   x |= 3;  std::cout<<x <<std::endl;   x |= 6;  std::cout<<x <<std::endl;

output :

3 7

how possible, related bit addition??

its bitwise or.

first case:

0011(3 in decimal) 0000(0 in decimal)

so, or of both is:

0011 or 0000 = 0011  = 2^0 + 2^1  = 3

for second case, or works follows:

0011 (3 in decimal)  0110 (6 in decimal)

output of or 0111 in decimal is:

0011 or 0110 = 0111  = 2^0 + 2^1 + 2^2  = 1+2+4  = 7

Bready