Robot Arms 2

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Points: 0.10
Time limit: 2.0s
Memory limit: 1G

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Problem type
Problem Statement

You are given a sequence ~A = (A_1, A_2, \dots, A_N)~ of length ~N~ consisting of positive integers, and integers ~x~ and ~y~ .
Determine whether it is possible to place ~N+1~ points ~p_1, p_2, \dots, p_N, p_{N+1}~ in the ~xy~ -coordinate plane to satisfy all of the following conditions. (It is allowed to place two or more points at the same coordinates.)

  • ~p_1 = (0, 0)~ .
  • ~p_2 = (A_1, 0)~ .
  • ~p_{N+1} = (x, y)~ .
  • The distance between the points ~p_i~ and ~p_{i+1}~ is ~A_i~ . ( ~1 \leq i \leq N~ )
  • The segments ~p_i p_{i+1}~ and ~p_{i+1} p_{i+2}~ form a ~90~ degree angle. ( ~1 \leq i \leq N - 1~ )
Constraints
  • ~2 \leq N \leq 10^3~
  • ~1 \leq A_i \leq 10~
  • ~|x|, |y| \leq 10^4~
  • All values in the input are integers.

Input

The input is given from Standard Input in the following format:

~N~ ~x~ ~y~ ~A_1~ ~A_2~ ~\dots~ ~A_N~

Output

If it is possible to place ~p_1, p_2, \dots, p_N, p_{N+1}~ to satisfy all of the conditions in the Problem Statement, print Yes ; otherwise, print No .


Sample Input 1
3 -1 1
2 1 3
Sample Output 1
Yes

The figure below shows a placement where ~p_1 = (0, 0)~ , ~p_2 = (2, 0)~ , ~p_3 = (2, 1)~ , and ~p_4 = (-1, 1)~ . All conditions in the Problem Statement are satisfied.


Sample Input 2
5 2 0
2 2 2 2 2
Sample Output 2
Yes

Letting ~p_1 = (0, 0)~ , ~p_2 = (2, 0)~ , ~p_3 = (2, 2)~ , ~p_4 = (0, 2)~ , ~p_5 = (0, 0)~ , and ~p_6 = (2, 0)~ satisfies all the conditions. Note that multiple points may be placed at the same coordinates.


Sample Input 3
4 5 5
1 2 3 4
Sample Output 3
No

Sample Input 4
3 2 7
2 7 4
Sample Output 4
No

Sample Input 5
10 8 -7
6 10 4 1 5 9 8 6 5 1
Sample Output 5
Yes

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