# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
601693 | Mazaalai | Meetings (IOI18_meetings) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include "meetings.h"
#include <bits/stdc++.h>
#define sz(x) (int)x.size()
#define ALL(x) x.begin(), x.end()
#define chmax(a, b) a=max(a,b)
#define chmin(a, b) a=min(a,b)
#define pb push_back
#define ff first
#define ss second
using namespace std;
using ll = long long;
using VI = vector <int>;
using PII = pair <int, int>;
int n, m, q;
const int N = 1e5+1;
const int M = 3*N
const int N1 = 5001;
ll dp[N1][N1];
int nums[N];
struct Node {
int l, r, mx;
} node[M];
Node merge(Node a, Node b) {
Node res = {a.l, b.r, max(a.mx, b.mx)};
if (a.l == a.mx && b.l == b.mx) {
int x = a.mx + b.mx;
res = {x, x, x};
} else if (a.l == a.mx) {
res.l = a.mx + b.l;
chmax(res.mx, res.l);
} else if (b.l == b.mx) {
res.r = a.r + b.mx;
chmax(res.mx, res.r);
}
return res;
}
void build(int l, int r, int head) {
if (l == r) {
int x = (nums[l] == 1);
node[head] = {x, x, x};
return;
}
int mid = (l+r)>>1;
build(l, mid, head*2+1);
build(mid+1, r, head*2+2);
node[head] = merge(node[head*2+1], node[head*2+2]);
}
Node zero = {0, 0, 0};
Node query(int l, int r, int L, int R, int head) {
if (l > R || L > r) return zero;
if (L <= l && r <= R) return node[head];
int mid = (l+r)>>1;
return merge(
query(l, mid, L, R, head*2+1),
query(mid+1, r, L, R, head*2+2)
);
}
vector<long long> minimum_costs(vector<int> h, vector<int> L, vector<int> R) {
n = sz(h);
q = sz(L);
// cout << n << ' ' << q << '\n';
vector<long long> ans(q, 1e18);
if (n < N1) {
for (int i = 0; i < n; i++) {
for (int j = i, cur = 0; j < n; j++) {
cur = max(cur, h[j]);
dp[i][j] = cur;
if (j > i) dp[i][j] += dp[i][j-1];
}
for (int j = i, cur = 0; j >= 0; j--) {
cur = max(cur, h[j]);
dp[i][j] = cur;
if (j < i) dp[i][j] += dp[i][j+1];
}
}
for (int i = 0; i < q; i++) {
int l = L[i], r = R[i];
ll& res = ans[i];
for (int mid = l; mid <= r; mid++) {
chmin(res, dp[mid][l]+dp[mid][r]-h[mid]);
}
}
return ans;
} else {
for (int i = 0; i < n; i++) nums[i] = h[i];
build(0, n-1, 0);
for (int i = 0; i < q; i++) {
ans[i] = query(0, n-1, L[i], R[i], 0).mx;
}
}
return ans;
}