/*
IOI 2008 Pyramid Base
- Case B = 0:
- Let r[l] be the right x-coordinate if the left x-coordinate of the pyramid base is l
- Notice how r[l] >= r[l - 1]
- This means we can use 2 pointers to find the largest r - l
- To find the maximum height of a pyramid with x-coordinates in the range [l, r], we can use
a segment tree that supports range increment and stores the maximum number of consecutive 0s
- We don't actually need lazy propagation because we only care about the number of consecutive 0s
- See SACO 2018 Stadium for a similar problem
- Complexity: O((N + P) log N)
- Case B > 0:
- Binary search for
*/
#include <bits/stdc++.h>
#define FOR(i, x, y) for (int i = x; i < y; i++)
using namespace std;
namespace no_remove {
struct Node {
int sm, range, mxl, mxr, mxt;
};
Node segtree[4000001];
vector<pair<int, int>> add[1000002], subtr[1000002];
void combine(int node, Node l, Node r) {
if (l.sm) l.mxl = l.mxr = l.mxt = 0;
if (r.sm) r.mxl = r.mxr = r.mxt = 0;
segtree[node] = {segtree[node].sm, l.range + r.range,
l.mxl + (l.mxl == l.range ? r.mxl : 0),
r.mxr + (r.mxl == r.range ? l.mxr : 0),
max({l.mxt, r.mxt, l.mxr + r.mxl})};
}
void build(int node, int l, int r) {
if (l == r) segtree[node] = {0, 1, 1, 1, 1};
else {
int mid = (l + r) / 2;
build(node * 2, l, mid);
build(node * 2 + 1, mid + 1, r);
combine(node, segtree[node * 2], segtree[node * 2 + 1]);
}
}
void update(int a, int b, int val, int node, int l, int r) {
if (l > b || r < a) return;
if (l >= a && r <= b) segtree[node].sm += val;
else {
int mid = (l + r) / 2;
update(a, b, val, node * 2, l, mid);
update(a, b, val, node * 2 + 1, mid + 1, r);
combine(node, segtree[node * 2], segtree[node * 2 + 1]);
}
}
void solve(int H, int W) {
add[H + 1].push_back({1, W});
int N, C;
cin >> N;
FOR(i, 0, N) {
int x1, y1, x2, y2;
cin >> x1 >> y1 >> x2 >> y2 >> C;
add[x1].push_back({y1, y2});
subtr[x2 + 1].push_back({y1, y2});
}
build(1, 1, W);
int ans = 0, rptr = 1;
FOR(lptr, 1, H + 1) {
for (pair<int, int> i : subtr[lptr]) update(i.first, i.second, -1, 1, 1, W);
while ((segtree[1].sm ? 0 : segtree[1].mxt) >= rptr - lptr) {
for (pair<int, int> i : add[rptr]) update(i.first, i.second, 1, 1, 1, W);
ans = max(ans, rptr++ - lptr);
}
}
cout << ans;
}
}
namespace yes_remove {
int lazy[4000001], segtree[4000001];
vector<tuple<int, int, int>> add[1000001], subtr[1000001];
void push_lazy(int node, int l, int r) {
segtree[node] += lazy[node];
if (l != r) {
lazy[node * 2] += lazy[node];
lazy[node * 2 + 1] += lazy[node];
}
lazy[node] = 0;
}
void update(int a, int b, int val, int node, int l, int r) {
push_lazy(node, l, r);
if (l > b || r < a) return;
if (l >= a && r <= b) {
lazy[node] = val;
push_lazy(node, l, r);
} else {
int mid = (l + r) / 2;
update(a, b, val, node * 2, l, mid);
update(a, b, val, node * 2 + 1, mid + 1, r);
segtree[node] = min(segtree[node * 2], segtree[node * 2 + 1]);
}
}
int query(int a, int b, int node, int l, int r) {
push_lazy(node, l, r);
if (l > b || r < a) return INT_MAX;
if (l >= a && r <= b) return segtree[node];
int mid = (l + r) / 2;
return min(query(a, b, node * 2, l, mid), query(a, b, node * 2 + 1, mid + 1, r));
}
bool check(int len, int H, int W, int B) {
fill(segtree + 1, segtree + 4 * W + 1, 0);
fill(lazy + 1, lazy + 4 * W + 1, 0);
FOR(i, 1, len) for (auto j : add[i]) update(get<0>(j), get<1>(j) + len, get<2>(j), 1, 1, W);
FOR(i, len, H + 1) {
for (auto j : add[i]) update(get<0>(j), get<1>(j) + len, get<2>(j), 1, 1, W);
for (auto j : subtr[i - len + 1]) update(get<0>(j), get<1>(j) + len, -get<2>(j), 1, 1, W);
if (query(len, W, 1, 1, W) <= B) return true;
}
return false;
}
void solve(int H, int W, int B) {
int N;
cin >> N;
FOR(i, 0, N) {
int x1, y1, x2, y2, c;
cin >> x1 >> y1 >> x2 >> y2 >> c;
add[x1].push_back({y1, y2, c});
subtr[x2 + 1].push_back({y1, y2, c});
}
int l = 1, r = min(H, W);
while (l != r) {
int mid = (l + r + 1) / 2;
if (check(mid, H, W, B)) l = mid;
else r = mid - 1;
}
cout << l;
}
}
int main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int H, W, B;
cin >> H >> W >> B;
if (B) yes_remove::solve(H, W, B);
else no_remove::solve(H, W);
return 0;
}
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
57 ms |
94328 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
56 ms |
94328 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
58 ms |
94328 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
60 ms |
94968 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
64 ms |
99456 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
105 ms |
135416 KB |
Output is correct |
| 2 |
Correct |
102 ms |
135416 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
103 ms |
135416 KB |
Output is correct |
| 2 |
Correct |
104 ms |
135532 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
79 ms |
94968 KB |
Output is correct |
| 2 |
Correct |
131 ms |
95096 KB |
Output is correct |
| 3 |
Incorrect |
107 ms |
94968 KB |
Output isn't correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
337 ms |
98680 KB |
Output is correct |
| 2 |
Incorrect |
588 ms |
98732 KB |
Output isn't correct |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1036 ms |
127480 KB |
Output is correct |
| 2 |
Runtime error |
280 ms |
193740 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
2108 ms |
127992 KB |
Output is correct |
| 2 |
Runtime error |
4528 ms |
257024 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1694 ms |
128376 KB |
Output is correct |
| 2 |
Runtime error |
4550 ms |
258832 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 3 |
Halted |
0 ms |
0 KB |
- |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
718 ms |
152440 KB |
Output is correct |
| 2 |
Correct |
411 ms |
110968 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
919 ms |
160372 KB |
Output is correct |
| 2 |
Correct |
908 ms |
156520 KB |
Output is correct |
| 3 |
Correct |
586 ms |
149440 KB |
Output is correct |
| # |
결과 |
실행 시간 |
메모리 |
Grader output |
| 1 |
Correct |
1194 ms |
167928 KB |
Output is correct |
| 2 |
Correct |
1340 ms |
165224 KB |
Output is correct |
| 3 |
Correct |
1357 ms |
164964 KB |
Output is correct |
| 4 |
Correct |
1196 ms |
163040 KB |
Output is correct |
| 5 |
Correct |
874 ms |
157908 KB |
Output is correct |
