#include <bits/stdc++.h>
using namespace std;
int n1, n2, k1, k2;
int pd[110][110][11][11];
int calc(int q1, int q2, int s1, int s2) {
  if (s1 > k1 || s2 > k2 || q1 > n1 || q2 > n2) return 0;
  if (q1 == n1 && q2 == n2) return 1;
  if (pd[q1][q2][s1][s2] != -1) return pd[q1][q2][s1][s2];
  int res = 0;
  if (s1)
    res = (calc(q1 + 1, q2, s1 + 1, 0) + calc(q1, q2 + 1, 0, 1)) % 100000000;
  else
    res = (calc(q1 + 1, q2, 1, 0) + calc(q1, q2 + 1, 0, s2 + 1)) % 100000000;
  return (pd[q1][q2][s1][s2] = res);
}
int main() {
  scanf("%d%d%d%d", &n1, &n2, &k1, &k2);
  memset(pd, -1, sizeof(pd));
  printf("%d\n", calc(0, 0, 0, 0));
  return 0;
}
