#include <bits/stdc++.h>
using namespace std;
long long dp[102][102][2];
int m = 100000000;
int main() {
  int n1, n2, k1, k2;
  cin >> n1 >> n2 >> k1 >> k2;
  int i, j, l1;
  for (i = 0; i <= n1; i++) {
    for (j = 0; j <= n2; j++) {
      if (i + j == 0)
        dp[i][j][0] = 1, dp[i][j][1] = 1;
      else if ((i == 0 && j > k2) || (j == 0 && i > k1))
        dp[i][j][0] = 0, dp[i][j][1] = 0;
      else if (i == 0)
        dp[i][j][0] = 0, dp[i][j][1] = 1;
      else if (j == 0)
        dp[i][j][0] = 1, dp[i][j][1] = 0;
      else {
        for (l1 = 1; l1 <= min(k1, i); l1++) {
          dp[i][j][0] = (dp[i][j][0] + dp[i - l1][j][1]) % m;
        }
        for (l1 = 1; l1 <= min(k2, j); l1++) {
          dp[i][j][1] = (dp[i][j][1] + dp[i][j - l1][0]) % m;
        }
      }
    }
  }
  cout << (dp[n1][n2][0] + dp[n1][n2][1]) % m;
  return 0;
}
