#include <bits/stdc++.h>
const double PI = 3.141592653589793238460;
using namespace std;
int limit_f, limit_h;
long long int dp[101][101][11][11];
int getAns(int f, int h, int k1, int k2) {
  if ((f + h) == 0) return 1;
  if (dp[f][h][k1][k2] != -1) return dp[f][h][k1][k2];
  int x = 0;
  if (f > 0 && k1 > 0) x = getAns(f - 1, h, k1 - 1, limit_h);
  int y = 0;
  if (h > 0 && k2 > 0) y = getAns(f, h - 1, limit_f, k2 - 1);
  return dp[f][h][k1][k2] = (x + y) % 100000000;
}
int main() {
  int t, n1, n2;
  t = 1;
  while (t--) {
    cin >> n1 >> n2 >> limit_f >> limit_h;
    for (int i = 0; i <= n1; i++) {
      for (int j = 0; j <= n2; j++) {
        for (int k = 0; k <= limit_f; k++) {
          for (int l = 0; l <= limit_h; l++) dp[i][j][k][l] = -1;
        }
      }
    }
    int ans = getAns(n1, n2, limit_f, limit_h);
    cout << ans << '\n';
  }
}
