#include <bits/stdc++.h>
using namespace std;
const int N = 2e4 + 34;
const long double EPS = 1e-12;
const int INF = 1e9 + 34;
const int md = 1e8;
int n2, n1, k1, k2, nb;
int ans;
int d[111][111][21];
int main() {
  cin >> n1 >> n2 >> k1 >> k2;
  d[0][0][10] = 1;
  for (int i = 0; i <= n1; i++)
    for (int j = 0; j <= n2; j++)
      for (int b = -k1; b <= k2; b++) {
        if (d[i][j][b + 10] == 0) continue;
        if (b > -k1) {
          nb = min(-1, b - 1);
          d[i + 1][j][nb + 10] = (d[i + 1][j][nb + 10] + d[i][j][b + 10]) % md;
        }
        if (b < k2) {
          nb = max(1, b + 1);
          d[i][j + 1][nb + 10] = (d[i][j + 1][nb + 10] + d[i][j][b + 10]) % md;
        }
      }
  int ans = 0;
  for (int b = -k1; b <= k2; b++) ans = (ans + d[n1][n2][b + 10]) % md;
  cout << ans;
  return 0;
}
