Initially, the entire coordinate plane is colored white. N rectangles were painted black. The i-th rectangle has bottom-left corner and top-right corner for 1≤i≤n1 le i le n1≤i≤n. You want to paint some of the black area white so that the remaining black part has a horizontal axis of symmetry. Find the maximum possible area of the remaining black part.
Initially, the entire coordinate plane is colored white. N rectangles were painted black. The i-th rectangle has bottom-left corner (i−1,Li)(i-1, L_i)(i−1,Li)and top-right corner (i,Ri)(i,R_i)(i,Ri) for 1≤i≤n1 le i le n1≤i≤n. You want to paint some of the black area white so that the remaining black part has a horizontal axis of symmetry. Find the maximum possible area of the remaining black part.
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