#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <memory.h>
#include <math.h>
#include <assert.h>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <algorithm>
#include <string>
#include <functional>
#include <vector>
#include <deque>
#include <utility>
#include <bitset>
#include <limits.h>
#include <time.h>
#include <functional>
#include <numeric>
using namespace std;
typedef long long ll;
typedef unsigned long long llu;
typedef double lf;
typedef unsigned int uint;
typedef long double llf;
typedef pair<int, int> pii;
typedef pair<ll, int> pli;
#define debug(format, ...) printf(format, __VA_ARGS__);
const int N_ = 1000500;
int N;
ll A[N_];
ll S1[N_], S2[N_];
ll cost (int l, int r) {
return (S2[r] - S2[l-1]) - (S1[r] - S1[l-1]) * (l-1);
}
struct line {
ll a, b;
line (ll a = 0, ll b = 0): a(a), b(b) { }
ll y (ll x) { return a * x + b; }
};
lf intersection (line p, line q) {
return (lf)(q.b - p.b) / (p.a - q.a);
}
struct CHT {
vector<line> stk;
void add (line p) { // 기울기 증가
while(stk.size() >= 2 && intersection(stk.back(), p) <= intersection(stk[stk.size()-2], p))
stk.pop_back();
stk.push_back(p);
}
ll get (ll x) { // 들쭉날쭉
int low = 0, high = (int)stk.size() - 2;
int pos = (int)stk.size() - 1;
ll ret = (ll)-1e18;
while(low <= high) {
int mid = (low + high) >> 1;
lf p = intersection(stk[mid], stk[mid + 1]);
ret = max(ret, stk[mid].y(x));
if(p > x) {
high = mid - 1;
pos = mid;
}else {
low = mid + 1;
}
}
for(int i = pos-5; i <= pos+5; i++) {
if(0 <= i && i < stk.size())
ret = max(ret, stk[i].y(x));
}
return ret;
}
} cht;
ll tb[N_];
int main() {
scanf("%d", &N);
for(int i = 1; i <= N; i++) {
scanf("%lld", A+i);
S1[i] = S1[i-1] + A[i];
S2[i] = S2[i-1] + i * A[i];
}
cht.add(line(0, 0));
for(int i = 1; i <= N; i++) {
tb[i] = max(tb[i-1], cht.get(-S1[i]) + S2[i]);
cht.add(line(i, (-S2[i] + S1[i] * i + tb[i])));
/*for(int j = 0; j < i; j++) {
ll val =
- (S1[i]) * j
+ (-S2[j] + S1[j] * j + tb[j])
+ S2[i];
tb[i] = max(tb[i], val);
}*/
}
printf("%lld\n", tb[N]);
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
32476 KB |
Output is correct |
2 |
Correct |
0 ms |
32476 KB |
Output is correct |
3 |
Correct |
1 ms |
32476 KB |
Output is correct |
4 |
Correct |
1 ms |
32476 KB |
Output is correct |
5 |
Correct |
0 ms |
32476 KB |
Output is correct |
6 |
Correct |
0 ms |
32476 KB |
Output is correct |
7 |
Correct |
0 ms |
32476 KB |
Output is correct |
8 |
Correct |
0 ms |
32476 KB |
Output is correct |
9 |
Correct |
0 ms |
32476 KB |
Output is correct |
10 |
Correct |
1 ms |
32476 KB |
Output is correct |
11 |
Correct |
0 ms |
32476 KB |
Output is correct |
12 |
Correct |
0 ms |
32476 KB |
Output is correct |
13 |
Correct |
0 ms |
32476 KB |
Output is correct |
14 |
Correct |
1 ms |
32476 KB |
Output is correct |
15 |
Correct |
0 ms |
32476 KB |
Output is correct |
16 |
Correct |
0 ms |
32476 KB |
Output is correct |
17 |
Correct |
0 ms |
32476 KB |
Output is correct |
18 |
Correct |
0 ms |
32476 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
15 ms |
32476 KB |
Output is correct |
2 |
Correct |
9 ms |
32476 KB |
Output is correct |
3 |
Correct |
16 ms |
32476 KB |
Output is correct |
4 |
Correct |
30 ms |
32476 KB |
Output is correct |
5 |
Correct |
31 ms |
32608 KB |
Output is correct |
6 |
Correct |
32 ms |
32476 KB |
Output is correct |
7 |
Correct |
128 ms |
32476 KB |
Output is correct |
8 |
Correct |
286 ms |
32476 KB |
Output is correct |
9 |
Correct |
259 ms |
32476 KB |
Output is correct |