B'One day Masha came home and noticed n mice in the corridor of her flat. Of course, she shouted loudly, so scared mice started to run to the holes in the corridor. The corridor can be represeted as a numeric axis with n mice and m holes on it. ith mouse is at the coordinate xi, and jth hole -- at coordinate pj. jth hole has enough room for cj mice, so not more than cj mice can enter this hole. What is the minimum sum of distances that mice have to go through so that they all can hide in the holes? If ith mouse goes to the hole j, then its distance is |xi xe2 x80 x89- xe2 x80 x89pj|. Print the minimum sum of distances. The first line contains two integer numbers n, m (1 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89n, xe2 x80 x89m xe2 x80 x89 xe2 x89 xa4 xe2 x80 x895000) -- the number of mice and the number of holes, respectively. The second line contains n integers x1, xe2 x80 x89x2, xe2 x80 x89..., xe2 x80 x89xn ( xe2 x80 x89- xe2 x80 x89109 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89xi xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89109), where xi is the coordinate of ith mouse. Next m lines contain pairs of integer numbers pj, xe2 x80 x89cj ( xe2 x80 x89- xe2 x80 x89109 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89pj xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89109, xe2 x80 x891 xe2 x80 x89 xe2 x89 xa4 xe2 x80 x89cj xe2 x80 x89 xe2 x89 xa4 xe2 x80 x895000), where pj is the coordinate of jth hole, and cj is the maximum number of mice that can hide in the hole j. Print one integer number -- the minimum sum of distances. If there is no solution, print -1 instead. '...