I'm trying to solve a nice and hard problem: Given n functions yi(x) = a0 + a1x + a2x^2 + a3x^3 and q queries. For each query, you are given an integer t and you are required to find out yi (i ≤ i ≤ n) that minimizes the value of yi(t).
I found a solution for this problem, using Li Chao tree: https://robert1003.github.io/2020/02/06/li-chao-segment-tree.html
But, I don't understand in a property: After sqrt(a0), two functions can intersect at most one time.
I need your help, please!