1 1 2 2
1000000000 1000000000
1
 1 1 1000000000 1000000000
100 1000000000
1
 1 1 10 18
5 6
5
 2 1 1000000000 2000000000
111 999999999
101 999999998
1
 4 13 400 600
13 30
1 19
1 160
1 113
58 73 15 319 194 362 128 157 336 162 77 90 96
 1 15 100 200
283 8
30 58 16 45 80 82 55 95 24 23 86 28 51 47 20
 3 2 300 400
24 68
13 65
15 113
127 177
 1 1 2 1
1 10
1
 4 2 7 15
10 9
4 4
9 3
4 10
1 6
 2 1 1000000000 2000000000
111 1000000000
101 1000000000
5
 2 1 1000000000 2000000000
111 999999998
101 999999998
1
 1 1 1000000000 1000000000
1 1000000000
1

1000000000
 -1
 5
 111
 1
 -1
 -1
 -1
 4
 101
 -1
 -1

#include <bits/stdc++.h>
void bubbleSortDown1(int a[], int b[], int n) {
  int loc, temp, i;
  for (loc = n - 1; loc >= 1; loc--)
    for (i = 0; i < loc; i++)
      if (a[i] > a[i + 1]) {
        temp = a[i];
        a[i] = a[i + 1];
        a[i + 1] = temp;
        temp = b[i];
        b[i] = b[i + 1];
        b[i + 1] = temp;
      }
}
int main() {
  int n, k, s, t;
  int i, j, sum = 0, time;
  scanf("%d%d%d%d", &n, &k, &s, &t);
  int v[n], g[n], p[k + 1];
  for (i = 0; i < n; i++) scanf("%d%d", &v[i], &g[i]);
  for (i = 0; i < k; i++) {
    scanf("%d", &p[i]);
    sum += p[i];
  }
  p[i] = s - sum;
  bubbleSortDown1(v, g, n);
  for (i = j = 0; i < n; i++) {
    time = 0;
    for (j = 0; j <= k; j++)
      if (g[i] * 2 >= p[j]) {
        if (g[i] / 2 >= p[j])
          time += p[j];
        else
          time += 3 * p[j] - g[i];
      }
    if (time <= t) {
      printf("%d", v[i]);
      break;
    }
  }
}
