#include <bits/stdc++.h>
using namespace std;
const int MOD = 100000000;
const int MAXN = 128;
const int MAXK = 12;
int dp[MAXN][MAXN][MAXK][MAXK];
inline void add(int& lhs, int rhs) {
  lhs += rhs;
  if (lhs >= MOD) {
    lhs -= MOD;
  }
}
int main() {
  int n1, n2, k1, k2;
  int ans = 0;
  scanf("%d%d%d%d", &n1, &n2, &k1, &k2);
  dp[0][0][0][0] = 1;
  for (int i1 = 0; i1 <= n1; ++i1) {
    for (int i2 = 0; i2 <= n2; ++i2) {
      for (int j1 = 0; j1 <= k1; ++j1) {
        for (int j2 = 0; j2 <= k2; ++j2) {
          if (dp[i1][i2][j1][j2] == 0) {
            continue;
          }
          if (i1 + 1 <= n1 && j1 + 1 <= k1) {
            add(dp[i1 + 1][i2][j1 + 1][0], dp[i1][i2][j1][j2]);
          }
          if (i2 + 1 <= n2 && j2 + 1 <= k2) {
            add(dp[i1][i2 + 1][0][j2 + 1], dp[i1][i2][j1][j2]);
          }
          if (i1 == n1 && i2 == n2) {
            add(ans, dp[i1][i2][j1][j2]);
          }
        }
      }
    }
  }
  printf("%d\n", ans);
  return 0;
}
