+1678 +1678 +1678 +1678 +1678 +1678 +1911 +1911 +1911 +1911 +1911 +1678 +1678 +1678 +1678 +1678 +1678 +1768 +1768 +1768 +1768 +1768 +1427 +1427 +1427 The function $f(x,y)$ gives an ordered pair as output. It is defined according to the following rules:
* If $x > 4$, $f(x,y) = (x - 4,y)$.
* If $x \le 4$ but $y > 4$, $f(x,y) = (x,y - 4)$.
* Otherwise, $f(x,y) = (x + y + 11,
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