#include <bits/stdc++.h>
#define se second
#define fs first
#define mp make_pair
#define pb push_back
#define ll long long
#define ii pair<ll,ll>
#define ld long double
#define SZ(v) (int)v.size()
#define ALL(v) v.begin(), v.end()
#define bit(msk, i) ((msk >> i) & 1)
#define iter(id, v) for(auto id : v)
#define rep(i,m,n) for(int i=(m); i<=(n); i++)
#define reb(i,m,n) for(int i=(m); i>=(n); i--)
using namespace std;
mt19937_64 rd(chrono :: steady_clock :: now().time_since_epoch().count());
ll Rand(ll l, ll r) { return uniform_int_distribution<ll> (l, r)(rd); }
const int N = 2e5 + 7;
const int Mod = 998244353;
const int szBL = 916;
const ll INF = 1e18;
const int BASE = 137;
int n;
ll a[N];
ll dp[N][2], pre[N];
struct fenwick_tree {
int Range;
ll fen[N];
void init (int n) {
Range = n;
rep (i, 1, n) fen[i] = -1;
}
void update (int pos, ll val) {
for (; pos <= Range; pos += pos & -pos) fen[pos] = max(fen[pos], val);
}
ll get (int pos ) {
ll res = -1;
for (; pos > 0; pos -= pos & -pos) res = max(res, fen[pos]);
return res;
}
}BIT;
void solution () {
cin >> n;
rep (i, 1, n) cin >> a[i];
rep (i, 1, n) pre[i] = pre[i - 1] + a[i];
memset(dp, 0x3f, sizeof dp);
dp[0][0] = 0;
int res = 0;
rep (k, 1, 50) {
rep (i, 0, n) dp[i][k & 1] = INF;
static vector<ll> vec; vec.clear();
rep (i, 0, n) vec.push_back(dp[i][k&1^1] + pre[i]);
sort (ALL(vec));
ll nval;
vec.resize (nval = unique(ALL(vec)) - vec.begin());
BIT.init(nval);
rep (i, 0, n) {
int posprei = upper_bound(ALL(vec), pre[i]) - vec.begin();
if (BIT.get(posprei) != -1) {
dp[i][k & 1] = pre[i] - BIT.get(posprei);
}
int pos = lower_bound(ALL(vec), dp[i][k&1^1] + pre[i]) - vec.begin() + 1;
BIT.update (pos, pre[i]);
}
rep (i, 0, n) {
if (dp[i][k & 1] < INF) res = k;
// cout << k<<","<<i<<" "<<dp[i][k & 1] <<"\n";
}
}
cout << res <<"\n";
}
#define file(name) freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout);
int main () {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
// file ("c");
int num_Test = 1;
// cin >> num_Test;
while (num_Test--)
solution();
}
/*
5 10
1 2
3 1
4 2
5 3
1 4
2 3
3 5
4 5
3 4
1 4
*/
Compilation message
segments.cpp: In function 'void solution()':
segments.cpp:59:44: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
59 | rep (i, 0, n) vec.push_back(dp[i][k&1^1] + pre[i]);
| ~^~
segments.cpp:69:52: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
69 | int pos = lower_bound(ALL(vec), dp[i][k&1^1] + pre[i]) - vec.begin() + 1;
| ~^~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
1 ms |
4444 KB |
Output is correct |
4 |
Correct |
1 ms |
4440 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
4564 KB |
Output is correct |
9 |
Correct |
1 ms |
4444 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
4444 KB |
Output is correct |
12 |
Correct |
1 ms |
4444 KB |
Output is correct |
13 |
Correct |
1 ms |
4444 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
1 ms |
4444 KB |
Output is correct |
4 |
Correct |
1 ms |
4440 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
4564 KB |
Output is correct |
9 |
Correct |
1 ms |
4444 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
4444 KB |
Output is correct |
12 |
Correct |
1 ms |
4444 KB |
Output is correct |
13 |
Correct |
1 ms |
4444 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
16 |
Correct |
2 ms |
4444 KB |
Output is correct |
17 |
Correct |
2 ms |
4444 KB |
Output is correct |
18 |
Incorrect |
2 ms |
4444 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
1 ms |
4444 KB |
Output is correct |
4 |
Correct |
1 ms |
4440 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
4564 KB |
Output is correct |
9 |
Correct |
1 ms |
4444 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
4444 KB |
Output is correct |
12 |
Correct |
1 ms |
4444 KB |
Output is correct |
13 |
Correct |
1 ms |
4444 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
16 |
Correct |
2 ms |
4444 KB |
Output is correct |
17 |
Correct |
2 ms |
4444 KB |
Output is correct |
18 |
Incorrect |
2 ms |
4444 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
1 ms |
4444 KB |
Output is correct |
4 |
Correct |
1 ms |
4440 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
4564 KB |
Output is correct |
9 |
Correct |
1 ms |
4444 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
4444 KB |
Output is correct |
12 |
Correct |
1 ms |
4444 KB |
Output is correct |
13 |
Correct |
1 ms |
4444 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
16 |
Correct |
2 ms |
4444 KB |
Output is correct |
17 |
Correct |
2 ms |
4444 KB |
Output is correct |
18 |
Incorrect |
2 ms |
4444 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Correct |
1 ms |
4444 KB |
Output is correct |
4 |
Correct |
1 ms |
4440 KB |
Output is correct |
5 |
Correct |
1 ms |
4444 KB |
Output is correct |
6 |
Correct |
1 ms |
4444 KB |
Output is correct |
7 |
Correct |
1 ms |
4444 KB |
Output is correct |
8 |
Correct |
1 ms |
4564 KB |
Output is correct |
9 |
Correct |
1 ms |
4444 KB |
Output is correct |
10 |
Correct |
1 ms |
4444 KB |
Output is correct |
11 |
Correct |
1 ms |
4444 KB |
Output is correct |
12 |
Correct |
1 ms |
4444 KB |
Output is correct |
13 |
Correct |
1 ms |
4444 KB |
Output is correct |
14 |
Correct |
1 ms |
4444 KB |
Output is correct |
15 |
Correct |
1 ms |
4444 KB |
Output is correct |
16 |
Correct |
2 ms |
4444 KB |
Output is correct |
17 |
Correct |
2 ms |
4444 KB |
Output is correct |
18 |
Incorrect |
2 ms |
4444 KB |
Output isn't correct |
19 |
Halted |
0 ms |
0 KB |
- |