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#include <algorithm>
#include <functional>
#include <iostream>
#include <vector>
using namespace std;

namespace {
  struct Cut {
    long long day;
    long long height;
    int end;

    Cut(long long d, long long h, int e):
      day{d}, height{h}, end{e}
    {
    }
  };

  template <typename Fun>
  int find_first(int a, int b, Fun&& f)
  {
    if (f(a)) return a;
    if (!f(b)) return b+1;
    while (b-a > 1) {
      int x = (a+b) / 2;
      if (f(x)) b = x;
      else a = x;
    }
    return b;
  }


  class Field {
    private:
      vector<int> growth;
      vector<long long> sum_growth;
      vector<Cut> cuts;

    public:
      Field(vector<int> growth_): growth{move(growth_)}
      {
        sort(growth.begin(), growth.end(), greater<int>());
        cuts.emplace_back(0, 0, growth.size());
        sum_growth.reserve(growth.size() + 1);
        sum_growth.push_back(0);
        for (auto const& g: growth) {
          sum_growth.push_back(sum_growth.back() + g);
        }
      }

      long long sum(int b, int e)
      {
        return sum_growth[e] - sum_growth[b];
      }

      long long cut(long long day, long long height)
      {
        long long res = 0;

        auto start = 0;
        while (!cuts.empty()) {
          auto const& c = cuts.back();

          int x = find_first(start, c.end-1, [&](int i) { return c.height + growth[i] * (day - c.day) < height; });
          res += (day - c.day) * sum(start, x);
          res -= (height - c.height) * (x - start);
          if (x < c.end) {
            if (x > 0) {
              cuts.emplace_back(day, height, x);
            }
            break;
          }
          start = c.end;
          cuts.pop_back();
        }
        if (cuts.empty()) {
          cuts.emplace_back(day, height, growth.size());
        }

        return res;
      }
  };
}

int main()
{
  iostream::sync_with_stdio(false);
  cin.tie(nullptr);

  int n, m;
  cin >> n >> m;

  vector<int> growth(n);
  for (auto& a: growth) {
    cin >> a;
  }

  Field f{move(growth)};
  for (int i = 0; i < m; ++i) {
    long long d, b;
    cin >> d >> b;
    cout << f.cut(d, b) << '\n';
  }

  return 0;
}