sum_{i = 1}^n sum_{j = 1}^n A_{i, j} x_i x_j leq 1
Bobo has a positive-definite n times n n×n matrix A A and an n n-dimension vector b b. He would like to find x_1, x_2, dots, x_n x 1 ,x 2 ,…,x n where x_1, x_2, dots, x_n in mathbb{R} x 1 ,x 2 ,…,x n ∈R, sum_{i = 1}^n sum_{j = 1}^n A_{i, j} x_i x_j leq 1 ∑ i=1 n ∑ j=1 n A i,j x i x j ≤1 sum_{i = 1}^n b_i x_i ∑ i=1 n b i x i is maximum. It can be shown that left(sum_{i = 1}^n b_i x_iright)^2 = frac{P}{Q} (∑ i=1 n b i x i ) 2 = Q P , which is rational. Find the value of P cdot Q^{-1} bmod 998244353 P⋅Q −1 mod998244353.
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