#include <bits/stdc++.h>
const double EPS = 1e-24;
const long long MOD = 100000000ll;
const double PI = 3.14159265359;
long long INF = 214748364542123113ll;
template <class T>
T Max2(T a, T b) {
  return a < b ? b : a;
}
template <class T>
T Min2(T a, T b) {
  return a < b ? a : b;
}
template <class T>
T Max3(T a, T b, T c) {
  return Max2(Max2(a, b), c);
}
template <class T>
T Min3(T a, T b, T c) {
  return Min2(Min2(a, b), c);
}
template <class T>
T Max4(T a, T b, T c, T d) {
  return Max2(Max2(a, b), Max2(c, d));
}
template <class T>
T Min4(T a, T b, T c, T d) {
  return Min2(Min2(a, b), Max2(c, d));
}
using namespace std;
int gcd(int a, int b) {
  if (b == 0) return a;
  a %= b;
  return gcd(b, a);
}
long long dp[110][110][2];
int main() {
  std::ios::sync_with_stdio(false);
  cin.tie(0);
  int n1, n2, k1, k2;
  cin >> n1 >> n2 >> k1 >> k2;
  dp[0][0][0] = dp[0][0][1] = 1;
  for (int i = 0; i <= n1; i++) {
    for (int j = 0; j <= n2; j++) {
      for (int k = 1; k <= k1; k++) {
        if (i + k <= n1)
          dp[i + k][j][0] = (dp[i + k][j][0] + dp[i][j][1]) % MOD;
      }
      for (int k = 1; k <= k2; k++) {
        if (j + k <= n2)
          dp[i][j + k][1] = (dp[i][j + k][1] + dp[i][j][0]) % MOD;
      }
    }
  }
  long long ans = dp[n1][n2][0] + dp[n1][n2][1];
  cout << ans % MOD << endl;
  return 0;
}
