2025-09-12 14:50:25 -03:00

139 lines
2.9 KiB
C++

/* Problem URL: https://codeforces.com/contest/2051/problem/D */
#include <bits/stdc++.h>
using namespace std;
#define V vector
#define rmin(a, b) a = min(a, b)
#define rmax(a, b) a = max(a, b)
#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
#define repv(i, v) for (auto &i : (v))
#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
#define sortv(v) sort(v.begin(), v.end())
#define all(v) (v).begin(), (v).end()
using vi = vector<int>;
using vvi = vector<vi>;
using vvvi = vector<vvi>;
using vvvvi = vector<vvvi>;
using ll = long long;
using vl = vector<ll>;
using vvl = vector<vl>;
using vvvl = vector<vvl>;
using vvvvl = vector<vvvl>;
template<class v>
auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
os << vec[0];
for (size_t i = 1; i < vec.size(); i++) {
os << ' ' << vec[i];
}
os << '\n';
return os;
}
template<class v>
auto operator>>(istream &is, vector<v> &vec)->istream& {
for (auto &i : vec) {
is >> i;
}
return is;
}
template<class v>
auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
for (auto &i : vec) {
os << i[0];
for (size_t j = 1; j < i.size(); j++) {
os << ' ' << i[j];
}
os << '\n';
}
return os;
}
template<class v>
auto operator>>(istream &is, vector<vector<v>> &vec)->istream& {
for (auto &i : vec) {
for (auto &j : i) {
is >> j;
}
}
return is;
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(nullptr);
int t;
cin >> t;
while (t--) {
ll n, x, y;
cin >> n >> x >> y;
vl items(n);
ll total = 0;
repv(i, items) {
cin >> i;
total += i;
}
sortv(items);
ll count = 0;
ll ans = 0;
for (size_t i = n - 1; i > 0; i--) {
int low = 0;
int high = i - 1;
int ansx = -1;
ll tmp = total - items[i];
while (low <= high) {
int mid = (low + high) / 2;
if (tmp - items[mid] >= x) {
ansx = mid;
low = mid + 1;
continue;
}
high = mid - 1;
}
if (ansx == -1) {
continue;
}
low = 0;
high = i - 1;
int ansy = -1;
while (low <= high) {
int mid = (low + high) / 2;
if (tmp - items[mid] <= y) {
ansy = mid;
high = mid - 1;
continue;
}
low = mid + 1;
}
if (ansy == -1) {
continue;
}
ans += (ansx - ansy) + 1;
}
cout << ans << '\n';
}
}