# Finding 2 Missing Numbers

Suppose that out of the integers from 1 to $$n$$ inclusive, you are given $$n-2$$ of them.

To identify which are the two missing numbers, Chris proposed the following solution :

Let the two numbers be $$x$$ and $$y$$.

The value of $$x+y$$ can be found by taking the sum of the first $$n$$ numbers and subtract by the sum of the $$n-2$$ given numbers.

The value of $$x\oplus y$$ can be found by taking the xor of the first $$n$$ numbers and xor it with the xor of the $$n-2$$ given numbers.

Solve the system of equation, then we can find the two missing numbers.

The solution is actually wrong. Which of the following cases can disprove Chris' solution?

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