2889：Unique Solution

Given N (1 ≤ N ≤ 1,000) integers a₁, a₂, …, a_N (|a_i| ≤ 100,000, 1 ≤ i ≤ N) and an integer M (1 ≤ M ≤ N), you are to determine whether there exists a unique set of 2M integers s₁, e₁, s₂, e₂, …, s_M, e_M (1 ≤ s₁ ≤ e₁ < s₂ ≤ e₂ < ... < s_M ≤ e_M ≤ N) such that the following sum is maximized:

__poj_jax_start__\sum_{i=1}^M\sum_{j=s_i}^{e_i}a_j__poj_jax_end__

The input contains multiple test cases. Each test case contains consists of two lines. The first line gives the integers N and M. The second line gives the integers a₁, a₂, …, a_N.

A pair of zeroes indicates the end of the input and should not be processed.

Output exactly one line for each test case. Output Yes if the answer is in the affirmative otherwise No.