CF BUDDY
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1949I · Disks

1800 · dfs and similar, geometry, graph matchings

Problem: You are given nn disks in the plane. The center of each disk has integer coordinates, and the radius of each disk is a positive integer. No two disks overlap in a region of positive area, but it is possible for disks to be tangent to each other.

Your task is to determine whether it is possible to change the radii of the disks in such a way that:

  • Disks that were tangent to each other remain tangent to each other.
  • No two disks overlap in a region of positive area.
  • The sum of all radii strictly decreases.

Input Format: The first line contains an integer nn (1n10001\le n \le 1000) — the number of disks.

The next nn lines contain three integers each. The ii-th of such lines contains xix_i, yiy_i (109xi,yi109-10^9 \leq x_i, y_i \leq 10^9), and rir_i (1ri1091 \leq r_i \leq 10^9) — the coordinates of the center, and the radius, of the ii-th disk.

Output Format: Print YES\texttt{YES} if it is possible to change the radii in the desired manner. Otherwise, print NO\texttt{NO}.

Note: In the first sample, one can decrease the radii of the first and third disk by 0.50.5, and increase the radius of the second disk by 0.50.5. This way, the sum of all radii decreases by 0.50.5. The situation before and after changing the radii is depicted below.

First sample (left) and a valid way to change the radii of the disks (right).

In the second sample, depicted below, there is no way to change the radii of the disks in the desired manner.

Second sample.

Sample Cases

Case 1

Input

5
0 2 1
0 0 1
4 -3 4
11 0 3
11 5 2

Output

YES

Case 2

Input

4
2 2 2
7 2 3
7 7 2
2 7 3

Output

NO

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