#include "bits/stdc++.h"
using namespace std;
#define ar array
#define int long long
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin>>n;
vector<int> a(n + 1);
for(int i=1;i<=n;i++) cin>>a[i];
vector<int> p(n);
for(int i=0;i<n;i++) p[i] = i + 1;
sort(p.begin(), p.end(), [&](int i, int j){
return (a[i] > a[j]);
});
vector<vector<int>> mx(n + 1, vector<int>(20));
for(int i=1;i<=n;i++) mx[i][0] = a[i];
for(int j=1;j<20;j++){
for(int i=1;i + (1 << (j - 1))<=n;i++){
mx[i][j] = max(mx[i][j-1], mx[i + (1 << (j - 1))][j-1]);
}
}
auto get = [&](int l, int r) -> int{
if(l > r) return -2e9;
int lg = __lg(r - l + 1);
return max(mx[l][lg], mx[r - (1 << lg) + 1][lg]);
};
auto check = [&](int l, int r){
if(l > r) swap(l, r);
int res = a[l] + a[r];
//~ cout<<l + 1<<" "<<(l + r) / 2<<", "<<max(1ll, l - (r - l))<<" "<<l - 1<<", "<<min(n + 1, r + (r - l))<<" "<<n<<endl;
res += max({get(l + 1, (l + r) / 2), get(max(1ll, l - (r - l)), l - 1), get(min(n + 1, r + (r - l)), n)});
return res;
};
int B = min(n, 1000ll);
int res = 0;
for(int i=0;i<B;i++){
for(int j=i+1;j<B;j++){
res = max(res, check(p[i], p[j]));
}
}
cout<<res<<"\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
160 ms |
42492 KB |
Output is correct |
2 |
Correct |
88 ms |
42468 KB |
Output is correct |
3 |
Correct |
89 ms |
42960 KB |
Output is correct |
4 |
Correct |
153 ms |
42940 KB |
Output is correct |
5 |
Correct |
156 ms |
42716 KB |
Output is correct |
6 |
Incorrect |
133 ms |
42716 KB |
Output isn't correct |
7 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Incorrect |
1 ms |
332 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |