#include <bits/stdc++.h>
using namespace std;
using ll = long long;
ll n, m, k1, k2;
int dp[101][101][11][11];
ll mod = 1e8;
ll solve(int N, int M, int K1, int K2) {
  if (N == 0 && M == 0) {
    return 1;
  }
  if (dp[N][M][K1][K2] != -1) {
    return dp[N][M][K1][K2];
  }
  ll ans = 0;
  if (N > 0 && K1 < k1) {
    ans += solve(N - 1, M, K1 + 1, 0);
  }
  if (M > 0 && K2 < k2) {
    ans += solve(N, M - 1, 0, K2 + 1);
  }
  ans %= mod;
  return dp[N][M][K1][K2] = ans;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cin >> n >> m >> k1 >> k2;
  for (int i = 0; i < 101; i++) {
    for (int j = 0; j < 101; j++) {
      for (int k = 0; k < 11; k++) {
        for (int l = 0; l < 11; l++) {
          dp[i][j][k][l] = -1;
        }
      }
    }
  }
  cout << solve(n, m, 0, 0) << '\n';
  return 0;
}
