#include <bits/stdc++.h>
using namespace std;
template <typename S, typename T>
ostream& operator<<(ostream& out, pair<S, T> const& p) {
  out << '(' << p.first << ", " << p.second << ')';
  return out;
}
template <typename T>
ostream& operator<<(ostream& out, vector<T> const& v) {
  long long l = v.size();
  for (long long i = 0; i < l - 1; i++) out << v[i] << ' ';
  if (l > 0) out << v[l - 1];
  return out;
}
template <typename T>
void trace(const char* name, T&& arg1) {
  cout << name << " : " << arg1 << "\n";
}
template <typename T, typename... Args>
void trace(const char* names, T&& arg1, Args&&... args) {
  const char* comma = strchr(names + 1, ',');
  cout.write(names, comma - names) << " : " << arg1 << " | ";
  trace(comma + 1, args...);
}
const int N = 5000 + 10;
long long dp[N][N];
int arr[N], n, m;
pair<int, int> h[N];
long long pre[N];
long long get_cost(int a, int b) { return pre[b] - pre[a - 1]; }
void f(int grp, int l, int r, int lk, int rk) {
  if (l > r) {
    return;
  }
  int mid = (l + r) / 2;
  int bestk = mid - 1;
  dp[grp][mid] = dp[grp - 1][mid];
  int curr = 0;
  for (int i = min(mid, rk); i >= lk && (mid - i + 1) <= h[grp].second; i--) {
    long long c = dp[grp - 1][i - 1] + get_cost(i, mid);
    if (dp[grp][mid] > c) {
      dp[grp][mid] = c;
      bestk = i;
    }
  }
  f(grp, l, mid - 1, lk, bestk);
  f(grp, mid + 1, r, bestk, rk);
}
int32_t main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    cin >> arr[i];
    dp[0][i] = 1000000000000000001;
  }
  sort(arr + 1, arr + n + 1);
  int lol = 0;
  for (int i = 1; i <= m; i++) {
    cin >> h[i].first >> h[i].second;
    lol += h[i].second;
  }
  if (lol < n) {
    cout << -1 << "\n";
    return 0;
  }
  sort(h + 1, h + m + 1);
  dp[0][0] = 0;
  for (int i = 1; i <= m; i++) {
    for (int j = 1; j <= n; j++) {
      pre[j] = abs(arr[j] - h[i].first) + pre[j - 1];
    }
    f(i, 1, n, 1, n);
  }
  cout << dp[m][n] << "\n";
  return 0;
}
