#include <bits/stdc++.h>
using namespace std;
const int maxn = 2e5 + 5;
int n, m, k, t;
int a[maxn];
int p[maxn];
int f[2005];
int read() {
  int x;
  scanf("%d", &x);
  return x;
}
int sum(int l, int r) { return a[r] - a[l + p[r - l + 1] - 1]; }
int main() {
  int i, j;
  int x, y;
  n = read();
  m = read();
  k = read();
  for (i = 1; i <= n; i++) {
    a[i] = read();
  }
  for (i = 1; i <= m; i++) {
    x = read();
    y = read();
    p[x] = max(p[x], y);
  }
  sort(a + 1, a + n + 1);
  for (i = 1; i <= n; i++) {
    a[i] += a[i - 1];
  }
  memset(f, 0x3f, sizeof(f));
  f[0] = 0;
  for (i = 1; i <= k; i++) {
    for (j = 0; j < i; j++) {
      f[i] = min(f[i], f[j] + sum(j + 1, i));
    }
  }
  printf("%d\n", f[k]);
  return 0;
}
