Weird full graph

You are given a weighted directed graph of $N$ vertices and $N^2$ edges, and an array $A$ of length $N$. Initially, every ordered pair of vertices $(u, v)$ is connected by a directed edge $u \to v$ of cost $A_u$ (this also includes self-loops). Then there were $M$ changes in edges' weights such that the weight of the directed edge $u\to v$ is now equal to $c$. You are asked to find the sum of