#include <bits/stdc++.h>
#define fr(i, a, b) for(int i = (a); i <= (b); ++i)
#define rf(i, a, b) for(int i = (a); i >= (b); --i)
#define fe(x, y) for(auto& x : y)
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define mt make_tuple
#define all(x) (x).begin(), (x).end()
#define pw(x) (1LL << (x))
#define sz(x) (int)(x).size()
using namespace std;
mt19937_64 rng(chrono::system_clock::now().time_since_epoch().count());
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<typename T>
using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
#define fbo find_by_order
#define ook order_of_key
template<typename T>
bool umn(T& a, T b) { return (a > b ? (a = b, 1) : 0); }
template<typename T>
bool umx(T& a, T b) { return (a < b ? (a = b, 1) : 0); }
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
template<typename T>
using ve = vector<T>;
const int N = 5e5 + 5;
int n;
int a[N];
ll pref[N];
//int dp[N][N];
//pii par[N][N];
//
//int brute1() {
// fr(i, 0, n) {
// fr(j, 0, n) {
// dp[i][j] = -1e9;
// }
// }
//
// fr(i, 1, n) {
// dp[i][1] = 1;
//
// rf(j, i, 1) {
// if(dp[i][j] != -1e9) {
// fr(nxt, i + 1, n) {
// if(pref[nxt] - pref[i] >= pref[i] - pref[j - 1]) {
// if(umx(dp[nxt][i + 1], dp[i][j] + 1)) {
// par[nxt][i + 1] = {i, j};
// }
// }
// }
// break;
// }
// }
// }
//
// int mx = 0;
// pii best;
// fr(i, 1, n) {
// fr(j, 1, n) {
// if(umx(mx, dp[i][j])) {
// best = {i, j};
// }
// }
// }
// ve<int> ans;
// while(1) {
// ans.pb(best.fi);
// if(best.se == 1) break;
// best = par[best.fi][best.se];
// }
// reverse(all(ans));
//// cout << "ans: ";
//// fe(x, ans) cout << x << " ";
//// cout << "\n";
//
// int prev = 0;
// fe(x, ans) {
//// cout << pref[x] - pref[prev] << " ";
// prev = x;
// }
//// cout << "\n";
//
// return mx;
//}
int solve() {
ve<int> dp(n + 1), cnt(n + 1);
fr(i, 0, n) dp[i] = -1e9, cnt[i] = -1e9;
fr(i, 1, n) {
if(umx(dp[i], 1)) {
cnt[i] = 1;
}
if(umx(dp[i + 1], dp[i])) {
cnt[i + 1] = cnt[i];
}
int l = i + 1;
int r = n;
while(l < r) {
int mid = l + ((r - l) >> 1);
if(pref[mid] - pref[i] < pref[i] - pref[dp[i] - 1]) {
l = mid + 1;
} else {
r = mid;
}
}
if(pref[l] - pref[i] >= pref[i] - pref[dp[i] - 1]) {
if(umx(dp[l], i + 1)) {
cnt[l] = cnt[i] + 1;
}
}
// ll sum = 0;
// fr(j, i + 1, n) {
// sum += a[j];
// if(sum >= pref[i] - pref[dp[i] - 1]) {
// break;
// }
// }
}
return *max_element(all(cnt));
}
int main() {
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
ios::sync_with_stdio(0);
cin.tie(0);
#else
// freopen("input.txt", "r", stdin);
// freopen("output.txt", "w", stdout);
ios::sync_with_stdio(0);
cin.tie(0);
#endif
cin >> n;
fr(i, 1, n) {
cin >> a[i];
// a[i] = rng() % int(1e6) + 1;
pref[i] = a[i] + pref[i - 1];
}
// fr(i, 1, n) cout << a[i] << " ";
// cout << "\n";
// cout << brute1() << "\n";
// cout << brute2() << "\n";
cout << solve() << "\n";
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
332 KB |
Output is correct |
20 |
Correct |
0 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
332 KB |
Output is correct |
23 |
Correct |
0 ms |
332 KB |
Output is correct |
24 |
Correct |
0 ms |
332 KB |
Output is correct |
25 |
Correct |
1 ms |
332 KB |
Output is correct |
26 |
Correct |
0 ms |
332 KB |
Output is correct |
27 |
Correct |
0 ms |
332 KB |
Output is correct |
28 |
Correct |
0 ms |
332 KB |
Output is correct |
29 |
Correct |
0 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
332 KB |
Output is correct |
20 |
Correct |
0 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
332 KB |
Output is correct |
23 |
Correct |
0 ms |
332 KB |
Output is correct |
24 |
Correct |
0 ms |
332 KB |
Output is correct |
25 |
Correct |
1 ms |
332 KB |
Output is correct |
26 |
Correct |
0 ms |
332 KB |
Output is correct |
27 |
Correct |
0 ms |
332 KB |
Output is correct |
28 |
Correct |
0 ms |
332 KB |
Output is correct |
29 |
Correct |
0 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
31 |
Correct |
1 ms |
332 KB |
Output is correct |
32 |
Correct |
1 ms |
336 KB |
Output is correct |
33 |
Correct |
1 ms |
332 KB |
Output is correct |
34 |
Correct |
1 ms |
332 KB |
Output is correct |
35 |
Correct |
1 ms |
332 KB |
Output is correct |
36 |
Correct |
1 ms |
332 KB |
Output is correct |
37 |
Correct |
1 ms |
332 KB |
Output is correct |
38 |
Correct |
1 ms |
332 KB |
Output is correct |
39 |
Correct |
1 ms |
332 KB |
Output is correct |
40 |
Correct |
1 ms |
332 KB |
Output is correct |
41 |
Correct |
1 ms |
332 KB |
Output is correct |
42 |
Correct |
1 ms |
332 KB |
Output is correct |
43 |
Correct |
1 ms |
332 KB |
Output is correct |
44 |
Correct |
0 ms |
332 KB |
Output is correct |
45 |
Correct |
1 ms |
332 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
332 KB |
Output is correct |
20 |
Correct |
0 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
332 KB |
Output is correct |
23 |
Correct |
0 ms |
332 KB |
Output is correct |
24 |
Correct |
0 ms |
332 KB |
Output is correct |
25 |
Correct |
1 ms |
332 KB |
Output is correct |
26 |
Correct |
0 ms |
332 KB |
Output is correct |
27 |
Correct |
0 ms |
332 KB |
Output is correct |
28 |
Correct |
0 ms |
332 KB |
Output is correct |
29 |
Correct |
0 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
31 |
Correct |
1 ms |
332 KB |
Output is correct |
32 |
Correct |
1 ms |
336 KB |
Output is correct |
33 |
Correct |
1 ms |
332 KB |
Output is correct |
34 |
Correct |
1 ms |
332 KB |
Output is correct |
35 |
Correct |
1 ms |
332 KB |
Output is correct |
36 |
Correct |
1 ms |
332 KB |
Output is correct |
37 |
Correct |
1 ms |
332 KB |
Output is correct |
38 |
Correct |
1 ms |
332 KB |
Output is correct |
39 |
Correct |
1 ms |
332 KB |
Output is correct |
40 |
Correct |
1 ms |
332 KB |
Output is correct |
41 |
Correct |
1 ms |
332 KB |
Output is correct |
42 |
Correct |
1 ms |
332 KB |
Output is correct |
43 |
Correct |
1 ms |
332 KB |
Output is correct |
44 |
Correct |
0 ms |
332 KB |
Output is correct |
45 |
Correct |
1 ms |
332 KB |
Output is correct |
46 |
Correct |
10 ms |
2556 KB |
Output is correct |
47 |
Correct |
12 ms |
2604 KB |
Output is correct |
48 |
Correct |
15 ms |
3012 KB |
Output is correct |
49 |
Correct |
12 ms |
3144 KB |
Output is correct |
50 |
Correct |
12 ms |
3292 KB |
Output is correct |
51 |
Correct |
15 ms |
3252 KB |
Output is correct |
52 |
Correct |
8 ms |
1736 KB |
Output is correct |
53 |
Correct |
5 ms |
1164 KB |
Output is correct |
54 |
Correct |
10 ms |
2440 KB |
Output is correct |
55 |
Correct |
13 ms |
3140 KB |
Output is correct |
56 |
Correct |
10 ms |
2660 KB |
Output is correct |
57 |
Correct |
11 ms |
2588 KB |
Output is correct |
58 |
Correct |
11 ms |
2680 KB |
Output is correct |
59 |
Correct |
10 ms |
2764 KB |
Output is correct |
60 |
Correct |
10 ms |
2764 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
332 KB |
Output is correct |
2 |
Correct |
0 ms |
332 KB |
Output is correct |
3 |
Correct |
0 ms |
204 KB |
Output is correct |
4 |
Correct |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
332 KB |
Output is correct |
6 |
Correct |
0 ms |
332 KB |
Output is correct |
7 |
Correct |
0 ms |
204 KB |
Output is correct |
8 |
Correct |
0 ms |
204 KB |
Output is correct |
9 |
Correct |
0 ms |
204 KB |
Output is correct |
10 |
Correct |
0 ms |
204 KB |
Output is correct |
11 |
Correct |
0 ms |
332 KB |
Output is correct |
12 |
Correct |
0 ms |
332 KB |
Output is correct |
13 |
Correct |
0 ms |
204 KB |
Output is correct |
14 |
Correct |
0 ms |
204 KB |
Output is correct |
15 |
Correct |
0 ms |
332 KB |
Output is correct |
16 |
Correct |
1 ms |
332 KB |
Output is correct |
17 |
Correct |
0 ms |
332 KB |
Output is correct |
18 |
Correct |
1 ms |
332 KB |
Output is correct |
19 |
Correct |
0 ms |
332 KB |
Output is correct |
20 |
Correct |
0 ms |
332 KB |
Output is correct |
21 |
Correct |
0 ms |
332 KB |
Output is correct |
22 |
Correct |
0 ms |
332 KB |
Output is correct |
23 |
Correct |
0 ms |
332 KB |
Output is correct |
24 |
Correct |
0 ms |
332 KB |
Output is correct |
25 |
Correct |
1 ms |
332 KB |
Output is correct |
26 |
Correct |
0 ms |
332 KB |
Output is correct |
27 |
Correct |
0 ms |
332 KB |
Output is correct |
28 |
Correct |
0 ms |
332 KB |
Output is correct |
29 |
Correct |
0 ms |
332 KB |
Output is correct |
30 |
Correct |
0 ms |
332 KB |
Output is correct |
31 |
Correct |
1 ms |
332 KB |
Output is correct |
32 |
Correct |
1 ms |
336 KB |
Output is correct |
33 |
Correct |
1 ms |
332 KB |
Output is correct |
34 |
Correct |
1 ms |
332 KB |
Output is correct |
35 |
Correct |
1 ms |
332 KB |
Output is correct |
36 |
Correct |
1 ms |
332 KB |
Output is correct |
37 |
Correct |
1 ms |
332 KB |
Output is correct |
38 |
Correct |
1 ms |
332 KB |
Output is correct |
39 |
Correct |
1 ms |
332 KB |
Output is correct |
40 |
Correct |
1 ms |
332 KB |
Output is correct |
41 |
Correct |
1 ms |
332 KB |
Output is correct |
42 |
Correct |
1 ms |
332 KB |
Output is correct |
43 |
Correct |
1 ms |
332 KB |
Output is correct |
44 |
Correct |
0 ms |
332 KB |
Output is correct |
45 |
Correct |
1 ms |
332 KB |
Output is correct |
46 |
Correct |
10 ms |
2556 KB |
Output is correct |
47 |
Correct |
12 ms |
2604 KB |
Output is correct |
48 |
Correct |
15 ms |
3012 KB |
Output is correct |
49 |
Correct |
12 ms |
3144 KB |
Output is correct |
50 |
Correct |
12 ms |
3292 KB |
Output is correct |
51 |
Correct |
15 ms |
3252 KB |
Output is correct |
52 |
Correct |
8 ms |
1736 KB |
Output is correct |
53 |
Correct |
5 ms |
1164 KB |
Output is correct |
54 |
Correct |
10 ms |
2440 KB |
Output is correct |
55 |
Correct |
13 ms |
3140 KB |
Output is correct |
56 |
Correct |
10 ms |
2660 KB |
Output is correct |
57 |
Correct |
11 ms |
2588 KB |
Output is correct |
58 |
Correct |
11 ms |
2680 KB |
Output is correct |
59 |
Correct |
10 ms |
2764 KB |
Output is correct |
60 |
Correct |
10 ms |
2764 KB |
Output is correct |
61 |
Correct |
53 ms |
11972 KB |
Output is correct |
62 |
Correct |
56 ms |
11972 KB |
Output is correct |
63 |
Correct |
63 ms |
12356 KB |
Output is correct |
64 |
Correct |
73 ms |
14688 KB |
Output is correct |
65 |
Correct |
64 ms |
14904 KB |
Output is correct |
66 |
Correct |
72 ms |
14936 KB |
Output is correct |
67 |
Correct |
61 ms |
11972 KB |
Output is correct |
68 |
Correct |
29 ms |
6068 KB |
Output is correct |
69 |
Correct |
49 ms |
11260 KB |
Output is correct |
70 |
Correct |
69 ms |
15068 KB |
Output is correct |
71 |
Correct |
44 ms |
12008 KB |
Output is correct |
72 |
Correct |
51 ms |
12308 KB |
Output is correct |
73 |
Correct |
50 ms |
12996 KB |
Output is correct |
74 |
Correct |
53 ms |
13324 KB |
Output is correct |
75 |
Correct |
53 ms |
13384 KB |
Output is correct |