#include <bits/stdc++.h>
using namespace std;
int n1, n2, k1, k2;
int dp[101][101][11][11];
int dfs(int n1, int n2, int q1, int q2) {
  if (n1 < 0 || n2 < 0 || q1 < 0 || q2 < 0) return 0;
  if (!n1 && !n2) return 1;
  if (dp[n1][n2][q1][q2] != -1) return dp[n1][n2][q1][q2];
  dp[n1][n2][q1][q2] =
      (dfs(n1 - 1, n2, q1 - 1, k2) + dfs(n1, n2 - 1, k1, q2 - 1)) % 100000000;
  return dp[n1][n2][q1][q2];
}
int main() {
  scanf("%d%d%d%d", &n1, &n2, &k1, &k2);
  memset(dp, -1, sizeof(dp));
  printf("%d\n", dfs(n1, n2, k1, k2));
  return 0;
}
