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#include <bits/stdc++.h>
using namespace std;
int n, l, r, ans, v[310];

inline int read() {
	int x = 0, f = 1;
	char ch = getchar();
	while (ch < '0' && ch > '9') {
		if (ch == '-') f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') {
		x = x * 10 + ch - '0';
		ch = getchar();
	}
	return x * f;
}

void dfs(int sum, int x) {
	if (x == n + 1) {
		if (sum <= r && sum >= l) ans ++;
		return ;
	}
	dfs(sum + v[x], x + 1);
	dfs(sum, x + 1);
}

int main() {
	n = read(), l = read(), r = read();
	for (int i = 1; i <= n; i ++) v[i] = read();
	dfs(0, 1);
	cout << ans;
	return 0;
}