#include<bits/stdc++.h>
using namespace std;
const int N = (int)5e5+7;
const int M = (int)2e5+7;
const int inf = (int)1e9+7;
int n, q, a[N];
int dp[5003][5003], mx[5003][5003];
pair<int, int> suf[N];
int l[N], r[N];
int ans;
void calc(int i, int j) {
if(j+(j-i)<=n) {
ans = max(ans, a[i]+a[j]+suf[j+(j-i)].first);
}
}
void solve3() {
cin >> q >> q >> q;
for(int i = n; i >= 1; --i) {
suf[i] = max(suf[i+1], {a[i], i});
}
stack<int> st;
for(int i = 1; i <= n; ++i) {
l[i] = i;
while(!st.empty() && a[st.top()]<a[i]) {
l[i]=l[st.top()];
st.pop();
}
st.push(i);
}
while(!st.empty()) {
continue;
}
for(int i = n; i >= 1; --i) {
r[i] = i;
while(!st.empty() && a[st.top()]<a[i]) {
r[i] = r[st.top()];
st.pop();
}
}
for(int i = 1; i < n; ++i) {
int j = r[i]+1;
if(j <= n) {
calc(i, j);
}
}
for(int i = 2; i < n; ++i) {
int j = l[i]-1;
if(j >= 1) {
calc(j, i);
}
}
cout << ans;
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cin >> n;
for(int i = 1; i <= n; ++i) {
cin >> a[i];
}
if(n>5000) {
solve3();
return 0;
}
for(int i = 1; i <= n; ++i) {
for(int j = i; j <= n; ++j) {
mx[i][j] = max(mx[i][j-1], a[j]);
}
}
for(int len = 3; len <= n; ++len) {
for(int i = 1; i <= n-len+1; ++i) {
int j = i+len-1;
dp[i][j]=max(dp[i+1][j], dp[i][j-1]);
int cur = a[i]+a[j];
int m = (i+j)/2;
cur += mx[i+1][m];
dp[i][j] = max(dp[i][j], cur);
}
}
cin >> q;
while(q--) {
int l, r;
cin >> l >> r;
cout << dp[l][r] << "\n";
}
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
1 ms |
3160 KB |
Output is correct |
3 |
Correct |
2 ms |
3164 KB |
Output is correct |
4 |
Correct |
1 ms |
3164 KB |
Output is correct |
5 |
Correct |
2 ms |
3164 KB |
Output is correct |
6 |
Correct |
1 ms |
3160 KB |
Output is correct |
7 |
Correct |
1 ms |
3164 KB |
Output is correct |
8 |
Correct |
1 ms |
3164 KB |
Output is correct |
9 |
Correct |
1 ms |
3164 KB |
Output is correct |
10 |
Correct |
1 ms |
3164 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
1 ms |
3160 KB |
Output is correct |
3 |
Correct |
2 ms |
3164 KB |
Output is correct |
4 |
Correct |
1 ms |
3164 KB |
Output is correct |
5 |
Correct |
2 ms |
3164 KB |
Output is correct |
6 |
Correct |
1 ms |
3160 KB |
Output is correct |
7 |
Correct |
1 ms |
3164 KB |
Output is correct |
8 |
Correct |
1 ms |
3164 KB |
Output is correct |
9 |
Correct |
1 ms |
3164 KB |
Output is correct |
10 |
Correct |
1 ms |
3164 KB |
Output is correct |
11 |
Correct |
455 ms |
152640 KB |
Output is correct |
12 |
Correct |
411 ms |
152404 KB |
Output is correct |
13 |
Correct |
422 ms |
152428 KB |
Output is correct |
14 |
Correct |
443 ms |
152716 KB |
Output is correct |
15 |
Correct |
420 ms |
152664 KB |
Output is correct |
16 |
Correct |
424 ms |
151904 KB |
Output is correct |
17 |
Correct |
442 ms |
151892 KB |
Output is correct |
18 |
Correct |
427 ms |
151940 KB |
Output is correct |
19 |
Correct |
443 ms |
152356 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
20 ms |
8796 KB |
Output is correct |
2 |
Correct |
18 ms |
8792 KB |
Output is correct |
3 |
Correct |
18 ms |
9816 KB |
Output is correct |
4 |
Correct |
19 ms |
8796 KB |
Output is correct |
5 |
Correct |
20 ms |
8796 KB |
Output is correct |
6 |
Correct |
18 ms |
8904 KB |
Output is correct |
7 |
Incorrect |
19 ms |
8540 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
1 ms |
3160 KB |
Output is correct |
3 |
Correct |
2 ms |
3164 KB |
Output is correct |
4 |
Correct |
1 ms |
3164 KB |
Output is correct |
5 |
Correct |
2 ms |
3164 KB |
Output is correct |
6 |
Correct |
1 ms |
3160 KB |
Output is correct |
7 |
Correct |
1 ms |
3164 KB |
Output is correct |
8 |
Correct |
1 ms |
3164 KB |
Output is correct |
9 |
Correct |
1 ms |
3164 KB |
Output is correct |
10 |
Correct |
1 ms |
3164 KB |
Output is correct |
11 |
Correct |
455 ms |
152640 KB |
Output is correct |
12 |
Correct |
411 ms |
152404 KB |
Output is correct |
13 |
Correct |
422 ms |
152428 KB |
Output is correct |
14 |
Correct |
443 ms |
152716 KB |
Output is correct |
15 |
Correct |
420 ms |
152664 KB |
Output is correct |
16 |
Correct |
424 ms |
151904 KB |
Output is correct |
17 |
Correct |
442 ms |
151892 KB |
Output is correct |
18 |
Correct |
427 ms |
151940 KB |
Output is correct |
19 |
Correct |
443 ms |
152356 KB |
Output is correct |
20 |
Correct |
20 ms |
8796 KB |
Output is correct |
21 |
Correct |
18 ms |
8792 KB |
Output is correct |
22 |
Correct |
18 ms |
9816 KB |
Output is correct |
23 |
Correct |
19 ms |
8796 KB |
Output is correct |
24 |
Correct |
20 ms |
8796 KB |
Output is correct |
25 |
Correct |
18 ms |
8904 KB |
Output is correct |
26 |
Incorrect |
19 ms |
8540 KB |
Output isn't correct |
27 |
Halted |
0 ms |
0 KB |
- |