#include "towers.h"
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e5 + 10;
int n, h[maxn], pref[maxn], peak_pos;
int cnt = 0;
int par[maxn], rnk[maxn];
int find_leader(int v)
{
return (v == par[v]) ? v : par[v] = find_leader(par[v]);
}
void unite(int v, int u)
{
v = find_leader(v);
u = find_leader(u);
if (v == u)
return;
if (rnk[v] < rnk[u])
swap(v, u);
rnk[v] += rnk[u];
par[u] = v;
}
int dp[maxn], bef[maxn], aft[maxn];
struct node
{
int max_number, min_number;
node(int _max_number = 0, int _min_number = 2e9)
{
max_number = _max_number;
min_number = _min_number;
}
};
node tree[4 * maxn];
node merge_node(node left, node right)
{
node comb;
comb.max_number = max(left.max_number, right.max_number);
comb.min_number = min(left.min_number, right.min_number);
return comb;
}
void build_tree(int root, int left, int right)
{
if (left == right)
{
tree[root] = node(h[left], h[left]);
return;
}
int mid = (left + right) / 2;
build_tree(root * 2, left, mid);
build_tree(root * 2 + 1, mid + 1, right);
tree[root] = merge_node(tree[root * 2], tree[root * 2 + 1]);
}
void update(int root, int left, int right, int pos, int val)
{
if (left == right)
{
tree[root] = val;
return;
}
int mid = (left + right) / 2;
if (pos <= mid)
update(root * 2, left, mid, pos, val);
else
update(root * 2 + 1, mid + 1, right, pos, val);
tree[root] = merge_node(tree[root * 2], tree[root * 2 + 1]);
}
node query(int root, int left, int right, int qleft, int qright)
{
if (left > qright || right < qleft)
return 0;
if (left >= qleft && right <= qright)
return tree[root];
int mid = (left + right) / 2;
return merge_node(query(root * 2, left, mid, qleft, qright),
query(root * 2 + 1, mid + 1, right, qleft, qright));
}
int find_rightmost(int root, int left, int right, int qleft, int qright, int val)
{
///cout << root << " " << left << " " << right << " " << qleft << " " << qright << " " << val << endl;
if (tree[root].max_number < val ||
left > qright || right < qleft)
return 0;
if (left == right)
return left;
int mid = (left + right) / 2;
if (left >= qleft && right <= qright)
{
if (tree[root * 2 + 1].max_number >= val)
return find_rightmost(root * 2 + 1, mid + 1, right, qleft, qright, val);
return find_rightmost(root * 2, left, mid, qleft, qright, val);
}
return max(find_rightmost(root * 2, left, mid, qleft, qright, val),
find_rightmost(root * 2 + 1, mid + 1, right, qleft, qright, val));
}
int find_leftmost(int root, int left, int right, int qleft, int qright, int val)
{
if (tree[root].max_number < val ||
left > qright || right < qleft)
return n + 1;
if (left == right)
return left;
int mid = (left + right) / 2;
if (left >= qleft && right <= qright)
{
if (tree[root * 2].max_number >= val)
return find_leftmost(root * 2, left, mid, qleft, qright, val);
return find_leftmost(root * 2 + 1, mid + 1, right, qleft, qright, val);
}
return max(find_leftmost(root * 2, left, mid, qleft, qright, val),
find_leftmost(root * 2 + 1, mid + 1, right, qleft, qright, val));
}
vector < pair < int, int > > val;
unordered_map < int, int > rev;
void init(int N, std::vector<int> H)
{
n = N;
for (int i = 0; i < n; i ++)
h[i + 1] = H[i], rev[H[i]] = i + 1;
for (int i = 1; i <= n; i ++)
if (h[i] > h[i - 1] && h[i] > h[i + 1])
cnt ++;
for (int i = 2; i < n; i ++)
{
pref[i] = pref[i - 1];
if (h[i] > h[i - 1] && h[i] > h[i + 1])
{
pref[i] ++, peak_pos = i;
}
}
build_tree(1, 1, n);
vector < int > st;
st.push_back(0);
for (int i = 1; i <= n; i ++)
{
while(!st.empty() && h[st.back()] >= h[i])
st.pop_back();
bef[i] = st.back();
st.push_back(i);
}
st.clear();
st.push_back(n + 1);
for (int i = n; i > 0; i --)
{
while(!st.empty() && h[st.back()] >= h[i])
st.pop_back();
aft[i] = st.back();
st.push_back(i);
}
for (int i = 1; i <= n; i ++)
{
///cout << bef[i] << " " << aft[i] << endl;
int h1 = 0, h2 = 0;
if (bef[i] != i - 1)
h1 = query(1, 1, n, bef[i] + 1, i - 1).max_number;
if (bef[i] == 0)
h1 = 2e9 + 10;
if (aft[i] != i + 1)
h2 = query(1, 1, n, i + 1, aft[i] - 1).max_number;
if (aft[i] == n + 1)
h2 = 2e9 + 10;
val.push_back({min(h1, h2) - h[i], i});
///cout << query(1, 1, n, bef[i] + 1)
}
sort(val.begin(), val.end());
//for (int v : val)
// cout << v << " ";
// cout << endl;
}
vector < int > act[maxn];
int cnt_query = 0;
int max_towers(int L, int R, int D)
{
L ++;
R ++;
cnt_query ++;
int lf = 0, rf = (int)(val.size()) - 1;
while(lf <= rf)
{
int mf = (lf + rf) / 2;
if (val[mf].first < D)
lf = mf + 1;
else
rf = mf - 1;
}
///vector < int > towers;
int leftmost = n + 1, rightmost = 0, ans = 0;
for (int i = lf; i < val.size(); i ++)
{
if (val[i].second >= L && val[i].second <= R)
{
ans ++;
///towers.push_back(val[i].second);
leftmost = min(leftmost, val[i].second);
rightmost = max(rightmost, val[i].second);
}
}
if (leftmost > rightmost)
{
int lowest_tower = rev[query(1, 1, n, L, R).min_number];
leftmost = lowest_tower;
rightmost = lowest_tower;
ans = 1;
}
int highest_tower = 0;
int La = find_rightmost(1, 1, n, 1, leftmost, h[leftmost] + D);
///cout << La << endl;
///cout << leftmost << " " << rightmost << endl;
for (int tower = leftmost - 1; tower >= L; tower --)
{
if (tower <= La && h[tower] + D <= highest_tower &&
highest_tower >= h[leftmost] + D)
{
ans ++;
break;
}
highest_tower = max(highest_tower, h[tower]);
}
highest_tower = 0;
int Ra = find_leftmost(1, 1, n, rightmost, n, h[rightmost] + D);
for (int tower = rightmost + 1; tower <= R; tower ++)
{
if (h[tower] >= h[rightmost] + D && tower < Ra)
{
cout << 1 / 0 << endl;
exit(0);
}
if (tower >= Ra && h[tower] + D <= highest_tower &&
highest_tower >= h[rightmost] + D)
{
ans ++;
break;
}
highest_tower = max(highest_tower, h[tower]);
}
return ans;
}
Compilation message
towers.cpp: In function 'int max_towers(int, int, int)':
towers.cpp:231:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
231 | for (int i = lf; i < val.size(); i ++)
| ~~^~~~~~~~~~~~
towers.cpp:271:23: warning: division by zero [-Wdiv-by-zero]
271 | cout << 1 / 0 << endl;
| ~~^~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
40 ms |
20244 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
8 ms |
11632 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
8 ms |
11632 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
88 ms |
28160 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
25 ms |
15724 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
8 ms |
11632 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Runtime error |
40 ms |
20244 KB |
Execution killed with signal 4 |
| 2 |
Halted |
0 ms |
0 KB |
- |
