#include <bits/stdc++.h>
using namespace std;
const int MOD = 100000000;
const int INF = 1000000007;
const long long INFLL = 1000000000000000000LL;
const int MAXN = 200009;
const double PI = 3.1415926535;
const double ep = 1e-8;
int n1, n2, k1, k2, dp[110][110][15][15];
int solve(int i, int j, int a, int b) {
  if (dp[i][j][a][b] != -1) return dp[i][j][a][b];
  int ans = 0;
  if (i == 0 && j == 0) ans = 1;
  if (i > 0 && a > 0) ans = (ans + solve(i - 1, j, a - 1, k2)) % MOD;
  if (j > 0 && b > 0) ans = (ans + solve(i, j - 1, k1, b - 1)) % MOD;
  return dp[i][j][a][b] = ans;
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> n1 >> n2 >> k1 >> k2;
  memset(dp, -1, sizeof dp);
  cout << solve(n1, n2, k1, k2) << "\n";
}
