Oh Those Rollers

A winch has a large steel plate holding $N$ rollers. The drive-roller, the ultimate source of power, sits at the origin $(0, 0)$. The drive-roller turns one other roller, that roller turns another, and so on, so power travels along a chain until the final roller is reached — a roller that is driven but drives no other roller.

Two rollers transmit power only when they touch on the outside: one roller drives another exactly when the distance between their centers equals the sum of their radii. That is, rollers $i$ and $j$ touch when $\sqrt{(x_i - x_j)^2 + (y_i - y_j)^2} = r_i + r_j$.

You are given the center coordinates $(x_i, y_i)$ and radius $r_i$ of every roller $i$. Find the coordinates of the last roller in the chain (the roller that is driven but drives no other roller). Every roller except the drive-roller is driven by exactly one other roller.

• $2 \le N \le 1080$
• $-5000 \le x_i \le 5000$, $-5000 \le y_i \le 5000$
• $3 \le r_i \le 1024$

• Line 1: a single integer $N$.
• Lines 2 to $N+1$: line $i+1$ describes roller $i$ with three space-separated integers $x_i$, $y_i$, and $r_i$.

• A single line with two space-separated integers: the $x$ and $y$ coordinates of the last roller in the chain of driven rollers.