#include <bits/stdc++.h>
bool isp(long long x) {
  if (x < 2) return 0;
  for (long long i = 2; i <= sqrt(x); i++) {
    if (x % i == 0) return 0;
  }
  return 1;
}
inline long long read() {
  long long x = 0, f = 1;
  char ch = getchar();
  while (!isdigit(ch)) {
    if (ch == '-') f = -1;
    ch = getchar();
  }
  while (isdigit(ch)) {
    x = x * 10 + ch - 48;
    ch = getchar();
  }
  return x * f;
}
long long gcd(long long x, long long y) { return !y ? x : gcd(y, x % y); }
using namespace std;
struct node {
  long long p, c;
} hole[5005];
long long n = read(), m = read(), x[5005], qzh[5005], sum[5005], dp[5005][5005];
long long cmp(node x, node y) { return x.p < y.p; }
int main() {
  for (int i = 0; i <= 5000; i++) {
    for (int j = 0; j <= 5000; j++) {
      dp[i][j] = 0x3f3f3f3f3f3f3f3f;
    }
  }
  dp[0][0] = 0;
  for (long long i = 1; i <= n; i++) x[i] = read();
  for (long long i = 1; i <= m; i++) hole[i].p = read(), hole[i].c = read();
  sort(x + 1, x + 1 + n);
  sort(hole + 1, hole + 1 + m, cmp);
  for (long long i = 1; i <= m; i++) qzh[i] = qzh[i - 1] + hole[i].c;
  if (qzh[m] < n) {
    puts("-1");
    return 0;
  }
  long long Q[5005], l, r;
  for (long long i = 1; i <= m; i++) {
    dp[i][0] = 0;
    l = 0, r = 1;
    Q[1] = 0;
    for (long long j = 1; j <= qzh[i] && j <= n; j++) {
      dp[i][j] = dp[i - 1][j];
      sum[j] = sum[j - 1] + abs(x[j] - hole[i].p);
      while ((j - Q[l] > hole[i].c) ||
             l <= r && dp[i - 1][Q[l]] - sum[Q[l]] > dp[i - 1][j] - sum[j])
        l++;
      Q[++r] = j;
      dp[i][j] = min(dp[i][j], sum[j] + dp[i - 1][Q[l]] - sum[Q[l]]);
    }
  }
  cout << dp[m][n];
  return 0;
}
