#include <bits/stdc++.h>
using namespace std;
long long dp[105][105][15][15];
long long n, m, p, q;
long long fun(long long i, long long j, long long l, long long r) {
  if (l < 0 || r < 0 || i < 0 || j < 0) return 0;
  if (i == 0 && j == 0) return 1;
  if (dp[i][j][l][r] != -1) return dp[i][j][l][r];
  dp[i][j][l][r] =
      (fun(i - 1, j, l - 1, q) + fun(i, j - 1, p, r - 1)) % 100000000;
  return dp[i][j][l][r];
}
void solve() {
  cin >> n >> m >> p >> q;
  for (long long int i = 0; i < n + 1; i++) {
    for (long long int j = 0; j < m + 1; j++) {
      for (long long int k = 0; k < p + 1; k++) {
        for (long long int l = 0; l < q + 1; l++) {
          dp[i][j][k][l] = -1;
        }
      }
    }
  }
  cout << fun(n, m, p, q) % 100000000;
  return;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int TESTS = 1;
  while (TESTS--) {
    solve();
  }
  cerr << "\nTime elapsed: " << 1000 * clock() / CLOCKS_PER_SEC << "ms\n";
  return 0;
}
