#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
using ll = long long;
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#define MAX(a, b) (((a) < (b)) ? (b) : (a))
int const nmax = 200000;
int const inf = 1000000005;
struct El{
int h;
int a;
int b;
} v[1 + nmax];
int _queries[1 + nmax][2];
int sol[1 + nmax];
vector<int> events[1 + nmax];
vector<pair<int,int>> queries[1 + nmax];
class SegmentTree{
private:
struct Node{
int result;
int smax;
Node operator + (Node const &a) const {
return {max(result, a.result), max(smax, a.smax)};
}
};
public:
vector<Node> aint;
vector<int> lazy;
SegmentTree(int n){
aint.resize(1 + 4 * n);
lazy.resize(1 + 4 * n);
}
void cleannode(int node, int from, int to){
if(from < to){
int mid = (from + to) / 2;
lazy[node * 2] = max(lazy[node * 2], lazy[node]);
lazy[node * 2 + 1] = max(lazy[node * 2 + 1], lazy[node]);
}
aint[node].result = max(aint[node].result, aint[node].smax + lazy[node]);
lazy[node] = 0;
}
void computenode(int node, int from, int to){
if(from < to){
int mid = (from + to) / 2;
aint[node] = aint[node * 2] + aint[node * 2 + 1];
}
}
void update(int node, int from, int to, int x, int y, int val){
if(x == from && to == y){
lazy[node] = max(lazy[node], val);
cleannode(node, from, to);
} else {
int mid = (from + to) / 2;
cleannode(node * 2, from, mid);
cleannode(node * 2 + 1, mid + 1, to);
if(x <= mid)
update(node * 2, from, mid, x, MIN(y, mid), val);
if(mid + 1 <= y)
update(node * 2 + 1, mid + 1, to, MAX(mid + 1, x), y, val);
computenode(node, from, to);
}
}
void setvalue(int node, int from, int to, int x, int val){
if(from < to){
int mid = (from + to) / 2;
cleannode(node * 2, from, mid);
cleannode(node * 2 + 1, mid + 1, to);
if(x <= mid)
setvalue(node * 2, from, mid, x, val);
else
setvalue(node * 2 + 1, mid + 1, to, x, val);
computenode(node, from, to);
} else {
cleannode(node, from, to);
aint[node] = {val, val};
}
}
int query(int node, int from, int to, int x, int y){
cleannode(node, from, to);
if(from == x && to == y)
return aint[node].result;
else {
int mid = (from + to) / 2;
if(x <= mid && y <= mid)
return query(node * 2, from, mid, x, y);
else if(mid + 1 <= x && mid + 1 <= y)
return query(node * 2 + 1, mid + 1, to, x, y);
else
return max(query(node * 2, from, mid, x, mid), query(node * 2 + 1, mid + 1, to, mid + 1, y));
}
}
};
void solve(int n, int q){
for(int i = 1;i <= n; i++) {
events[i].clear();
queries[i].clear();
}
for(int i = 1; i <= n; i++) {
if(i + v[i].a <= n)
events[i + v[i].a].push_back(i);
if(i + v[i].b + 1 <= n)
events[i + v[i].b + 1].push_back(-i);
}
for(int i = 1; i <= q; i++)
queries[_queries[i][1]].push_back({_queries[i][0], i});
SegmentTree aint(1 + n);
for(int i = 1; i <= n; i++)
aint.setvalue(1, 1, n, i, -inf);
for(int i = 1; i <= n; i++){
for(int h = 0; h < events[i].size(); h++){
int id = events[i][h];
if(0 < id)
aint.setvalue(1, 1, n, id, -v[id].h);
else
aint.setvalue(1, 1, n, -id, -inf);
}
int x = max(1, i - v[i].b);
int y = i - v[i].a;
if(x <= y)
aint.update(1, 1, n, x, y, v[i].h);
for(int h = 0; h < queries[i].size(); h++){
int pos = queries[i][h].second;
sol[pos] = max(sol[pos], aint.query(1, 1, n, queries[i][h].first, i));
}
}
}
int oth(int n, int pos){
return n - pos + 1;
}
int cost(int x, int y){
int dist = fabs(x - y);
if(max(v[x].a, v[y].a) <= dist && dist <= min(v[x].b, v[y].b))
return fabs(v[x].h - v[y].h);
return -1;
}
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
int n;
cin >> n;
for(int i = 1;i <= n; i++)
cin >> v[i].h >> v[i].a >> v[i].b;
int q;
cin >> q;
for(int i = 1;i <= q; i++)
cin >> _queries[i][0] >> _queries[i][1];
for(int i = 1;i <= q; i++)
sol[i] = -1;
solve(n, q);
for(int i = 1;i <= n; i++)
if(i < oth(n, i))
swap(v[i], v[oth(n, i)]);
for(int i = 1;i <= q; i++) {
_queries[i][0] = oth(n, _queries[i][0]);
_queries[i][1] = oth(n, _queries[i][1]);
swap(_queries[i][0], _queries[i][1]);
}
solve(n, q);
for(int i = 1;i <= q; i++)
cout << sol[i] << '\n';
return 0;
}
Compilation message
antennas.cpp: In member function 'void SegmentTree::cleannode(int, int, int)':
antennas.cpp:45:11: warning: unused variable 'mid' [-Wunused-variable]
int mid = (from + to) / 2;
^~~
antennas.cpp: In member function 'void SegmentTree::computenode(int, int, int)':
antennas.cpp:55:11: warning: unused variable 'mid' [-Wunused-variable]
int mid = (from + to) / 2;
^~~
antennas.cpp: In function 'void solve(int, int)':
antennas.cpp:129:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int h = 0; h < events[i].size(); h++){
~~^~~~~~~~~~~~~~~~~~
antennas.cpp:142:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int h = 0; h < queries[i].size(); h++){
~~^~~~~~~~~~~~~~~~~~~
antennas.cpp: In function 'int cost(int, int)':
antennas.cpp:154:14: error: 'fabs' was not declared in this scope
int dist = fabs(x - y);
^~~~
antennas.cpp:154:14: note: suggested alternative: 'labs'
int dist = fabs(x - y);
^~~~
labs
