Why does x[y] == y[x] in c++? [duplicate]

Answer 1

Because all of the following are same:

x[y] == y[x] == *(x+y) == *(y+x)

Answer 2

Because x[y] is just another way to say *(x + y), and that is the same as *(y + x).

Answer 3

It is always true (for normal operator==)

a[i]  --> *(a+i) --> *(i+a) --> i[a]

since int is intrinsic and has commutative operator==, this will always be true