Segment Tree Course : CodeNCode Youtube (30 July 2020 : Merge Sort Tree practice problem added)

I got AC for K-Query in Spoj, where same code is giving TLE on Codeforces.

Submission link on Codeforces:
https://codeforces.com/group/FLVn1Sc504/contest/274496/submission/98996257

Code:
#include <bits/stdc++.h>
#include <ext/rope>

#define pb push_back
#define ll long long
#define endl “\n”
#define MX 30005

#define W(t) while(t–)
#define all(v) v.begin(),v.end()
#define gcd(a,b) __gcd(a,b)
#define lcm(a,b) (a*b)/gcd(a,b)
#define rep(i,a,b) for(ll i = a; i <= b; i++)

using namespace std;
using namespace __gnu_cxx;

int a[MX], n, q, k;
vector segTree[4*MX];

void build(int node, int b, int e)
{
if (b == e) {
segTree[node].pb(a[b]);
return;
}

int mid = (b + e) / 2;
int left = node << 1;
int right = (node << 1) + 1;

build(left, b, mid);
build(right, mid + 1, e);

int i = 0, j = 0;

while (i < segTree[left].size() && j < segTree[right].size()) {
	if (segTree[left][i] <= segTree[right][j])
		segTree[node].pb(segTree[left][i]), i++;
	else
		segTree[node].pb(segTree[right][j]), j++;
}
while (i < segTree[left].size())
	segTree[node].pb(segTree[left][i]), i++;
while (j < segTree[right].size())
	segTree[node].pb(segTree[right][j]), j++;

}
int Query(int node, int b, int e, int l, int r, int k)
{
if (b > r || e < l) return 0;

if (b >= l && e <= r) {
	int indx = upper_bound(all(segTree[node]), k) - segTree[node].begin();
	if (indx == segTree[node].size()) return 0;
	else return (segTree[node].size() - indx);
}
int mid = (b + e) / 2;
int left = node << 1;
int right = (node << 1) + 1;

int r1 = Query(left, b, mid, l, r, k);
int r2 = Query(right, mid + 1, e, l, r, k);

return r1 + r2;

}
int main()
{
ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0);

cin >> n;
rep(i, 1, n) cin >> a[i];
build(1, 1, n);

cin >> q;

W(q)
{
	int l, r, k; cin >> l >> r >> k;
	cout << Query(1, 1, n, l, r, k) << endl;
}
return 0;

}
Any kind of help would be obliged. Thank you. :slight_smile: