#P10640. BZOJ2356 不等式

BZOJ2356 不等式

Problem Description

There are many inequalities in mathematics. For example, when x,y>0x,y>0:

x2+y22xyx^2+y^2 \geq 2xy x3+y3x2y+xy2x^3+y^3 \geq x^2y+xy^2

You are given two homogeneous bivariate polynomials f(x,y)f(x,y) and g(x,y)g(x,y), both with non-negative coefficients. Determine whether there exist A,r>0A,r>0 such that for any x,y>0x,y>0, the following always holds: f(x,y)Ag(x,y)rf(x,y)\geq Ag(x,y)^r.

Input Format

The input contains multiple test cases. Adjacent test cases are separated by one blank line.

Each test case contains two lines.

The first line contains n+2n+2 non-negative integers n,a0,a1,,ann,a_0,a_1,\dots,a_n, where the aia_i are not all 00, representing f(x,y)=a0xn+a1xn1y++anynf(x,y)=a_0x^n+a_1x^{n-1}y+\dots+a_ny^n.

The second line contains m+2m+2 non-negative integers m,b0,b1,,bmm,b_0,b_1,\dots,b_m, where the bib_i are not all 00, representing g(x,y)=b0xm+b1xm1y++bmymg(x,y)=b_0x^m+b_1x^{m-1}y+\dots+b_my^m.

Output Format

For each test case, output one line. If such A,rA,r exist, output YES; otherwise, output NO.

1 1 1
2 0 1 0

2 1 1 1
3 1 0 0 1

5 1 0 0 1 0 0
5 0 0 1 0 0 1
YES
YES
NO

Hint

Sample Explanation

  • For the first sample, x+y2xyx+y \geq \sqrt{2xy}.
  • For the second sample, x2+xy+y2(x3+y3)23x^2+xy+y^2\geq \sqrt[3]{(x^3+y^3)^2}. This is easy to verify after expansion.
  • For the third sample, assume the opposite: x5+x2y3A(x3y2+y5)rx^5+x^2y^3 \geq A(x^3y^2+y^5)^r holds for all positive x,yx,y. Let x=yx=y, then 2x5A(2x5)r2x^5\geq A(2x^5)^r. If r>1r>1, the inequality fails when xx is large enough; if r<1r<1, the inequality fails when xx is small enough, so r=1r=1. Then let x=1x=1, we get 1+y3A(y2+y5)1+y^3 \geq A(y^2+y^5), i.e., 1Ay21\geq Ay^2, which cannot hold for all positive yy. Therefore, such A,rA,r do not exist.

Constraints

There are at most 100100 test cases, and 1n,m1001\leq n,m\leq 100. The coefficients are at most 10410^4.

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