#include <bits/stdc++.h>
using namespace std;
const int maxN = 2005;
int n, h, l, r, a[maxN];
int dp[maxN][maxN];
inline int getint() {
  int num = 0, bj = 1;
  char c = getchar();
  while (c < '0' || c > '9') {
    if (c == EOF) return EOF;
    bj = (c == '-' || bj == -1) ? -1 : 1, c = getchar();
  }
  while (c >= '0' && c <= '9') num = num * 10 + c - '0', c = getchar();
  return num * bj;
}
void init() {
  cin >> n >> h >> l >> r;
  for (int i = 1; i <= n; ++i) {
    a[i] = getint();
  }
}
int cor(int x) { return (x % h + h) % h; }
void solve() {
  memset(dp, -1, sizeof(dp));
  int ans = -1;
  (a[1] >= l && a[1] <= r)                     ? dp[1][a[1]] = 1,
                             ans = max(ans, 1) : dp[1][a[1]] = 0,
                             ans = max(ans, 0);
  (a[1] - 1 >= l && a[1] - 1 <= r)
      ? dp[1][a[1] - 1] = 1,
                     ans = max(ans, 1) : dp[1][a[1] - 1] = 0, ans = max(ans, 0);
  for (int i = 2; i <= n; ++i) {
    for (int j = 0; j < h; ++j) {
      if (dp[i - 1][cor(j - a[i])] == -1 && dp[i - 1][cor(j - a[i] + 1)] == -1)
        continue;
      dp[i][j] = max(dp[i - 1][cor(j - a[i])], dp[i - 1][cor(j - a[i] + 1)]);
      if (j >= l && j <= r) dp[i][j]++;
      ans = max(ans, dp[i][j]);
    }
  }
  cout << ans << endl;
}
int main() {
  init();
  solve();
}
