You are given a complete graph with n nodes. There are two values associated with each node i, denoted by ai and bi.
The weight of the edge between two nodes i and j is denoted by wij=|aibj−ajbi|.
Find the sum of the square of weights of all the edges. Formally, find the value n∑i=1n∑j=i+1w2ij.
Input format
Output format
Print a single integer denoting the required value (mod 109+7).
Constraints
2≤n≤106−1015≤ai,bi≤1015
S=w212+w213+w223=32+12+32=19