#include <bits/stdc++.h>
#include "molecules.h"
using namespace std;
#define MASK(x) (1LL << (x))
#define BIT(x, i) (((x) >> (i)) & 1)
#define ALL(x) (x).begin(), (x).end()
#define REP(i, n) for (int i = 0, _n = n; i < _n; ++i)
#define FOR(i, a, b) for (int i = (a), _b = (b); i <= _b; ++i)
#define FORD(i, a, b) for (int i = (a), _b = (b); i >= _b; --i)
#define FORE(i, a, b) for (int i = (a), _b = (b); i < _b; ++i)
#define debug(...) "[" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "
#define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
template <class A, class B> bool minimize(A &a, B b) { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b) { if (a < b) { a = b; return true; } return false; }
vector <int> find_subset(int L, int R, vector <int> w) {
int n = (int) w.size();
vector <pair <int, int>> a;
vector <int> ans;
for (int i = 0; i < n; ++i) a.emplace_back(w[i], i);
sort(a.begin(), a.end());
int pr = 0, pl = 0;
long long sum = 0;
while(pr < n) {
sum += a[pr++].first;
while(sum > L) sum -= a[pl++].first;
if(L <= sum && sum <= R) break;
}
while(pl < n && sum > R) sum -= a[pl++].first;
if(L <= sum && sum <= R) {
for (int i = pl; i < pr; ++i) ans.push_back(a[i].second);
}
return ans;
}
#ifdef LOCAL
#include <cstdio>
#include <vector>
#include <cassert>
int main() {
freopen("TASK.inp", "r", stdin);
freopen("TASK.out", "w", stdout);
int n, l, u;
assert(3 == scanf("%d %d %d", &n, &l, &u));
std::vector<int> w(n);
for (int i = 0; i < n; i++)
assert(1 == scanf("%d", &w[i]));
std::vector<int> result = find_subset(l, u, w);
printf("%d\n", (int)result.size());
for (int i = 0; i < (int)result.size(); i++)
printf("%d%c", result[i], " \n"[i == (int)result.size() - 1]);
}
#endif // LOCAL
// Dream it. Wish it. Do it.
