#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 = 5e5 + 7;
const int Mod = 998244353;
const int szBL = 916;
const ll INF = 1e17;
const int BASE = 137;
int n;
ll a[N];
ll pre[N];
pair<ll,ll> dp[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 (i, 1, n) {
int lf = 0, rt = i - 1;
while (lf < rt) {
int mid = lf + rt + 1 >> 1;
if (dp[mid].fs <= pre[i] - pre[mid]) lf = mid;
else rt = mid - 1;
}
dp[i] = {pre[i] - pre[lf], dp[lf].se + 1};
}
cout << dp[n].se<<"\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:53:31: warning: 'void* memset(void*, int, size_t)' writing to an object of type 'struct std::pair<long long int, long long int>' with no trivial copy-assignment [-Wclass-memaccess]
53 | memset(dp, 0x3f, sizeof dp);
| ^
In file included from /usr/include/c++/10/bits/stl_algobase.h:64,
from /usr/include/c++/10/bits/specfun.h:45,
from /usr/include/c++/10/cmath:1927,
from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:41,
from segments.cpp:1:
/usr/include/c++/10/bits/stl_pair.h:211:12: note: 'struct std::pair<long long int, long long int>' declared here
211 | struct pair
| ^~~~
segments.cpp:59:31: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
59 | int mid = lf + rt + 1 >> 1;
| ~~~~~~~~^~~
segments.cpp:55:9: warning: unused variable 'res' [-Wunused-variable]
55 | int res = 0;
| ^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
11868 KB |
Output is correct |
2 |
Correct |
2 ms |
11868 KB |
Output is correct |
3 |
Correct |
2 ms |
11868 KB |
Output is correct |
4 |
Correct |
2 ms |
11868 KB |
Output is correct |
5 |
Correct |
2 ms |
11840 KB |
Output is correct |
6 |
Correct |
2 ms |
11864 KB |
Output is correct |
7 |
Correct |
2 ms |
11876 KB |
Output is correct |
8 |
Correct |
2 ms |
11864 KB |
Output is correct |
9 |
Correct |
2 ms |
11864 KB |
Output is correct |
10 |
Correct |
2 ms |
11864 KB |
Output is correct |
11 |
Correct |
2 ms |
11868 KB |
Output is correct |
12 |
Correct |
2 ms |
11868 KB |
Output is correct |
13 |
Correct |
2 ms |
11864 KB |
Output is correct |
14 |
Correct |
2 ms |
11864 KB |
Output is correct |
15 |
Correct |
2 ms |
11864 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
11868 KB |
Output is correct |
2 |
Correct |
2 ms |
11868 KB |
Output is correct |
3 |
Correct |
2 ms |
11868 KB |
Output is correct |
4 |
Correct |
2 ms |
11868 KB |
Output is correct |
5 |
Correct |
2 ms |
11840 KB |
Output is correct |
6 |
Correct |
2 ms |
11864 KB |
Output is correct |
7 |
Correct |
2 ms |
11876 KB |
Output is correct |
8 |
Correct |
2 ms |
11864 KB |
Output is correct |
9 |
Correct |
2 ms |
11864 KB |
Output is correct |
10 |
Correct |
2 ms |
11864 KB |
Output is correct |
11 |
Correct |
2 ms |
11868 KB |
Output is correct |
12 |
Correct |
2 ms |
11868 KB |
Output is correct |
13 |
Correct |
2 ms |
11864 KB |
Output is correct |
14 |
Correct |
2 ms |
11864 KB |
Output is correct |
15 |
Correct |
2 ms |
11864 KB |
Output is correct |
16 |
Correct |
2 ms |
11868 KB |
Output is correct |
17 |
Incorrect |
2 ms |
11868 KB |
Output isn't correct |
18 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
11868 KB |
Output is correct |
2 |
Correct |
2 ms |
11868 KB |
Output is correct |
3 |
Correct |
2 ms |
11868 KB |
Output is correct |
4 |
Correct |
2 ms |
11868 KB |
Output is correct |
5 |
Correct |
2 ms |
11840 KB |
Output is correct |
6 |
Correct |
2 ms |
11864 KB |
Output is correct |
7 |
Correct |
2 ms |
11876 KB |
Output is correct |
8 |
Correct |
2 ms |
11864 KB |
Output is correct |
9 |
Correct |
2 ms |
11864 KB |
Output is correct |
10 |
Correct |
2 ms |
11864 KB |
Output is correct |
11 |
Correct |
2 ms |
11868 KB |
Output is correct |
12 |
Correct |
2 ms |
11868 KB |
Output is correct |
13 |
Correct |
2 ms |
11864 KB |
Output is correct |
14 |
Correct |
2 ms |
11864 KB |
Output is correct |
15 |
Correct |
2 ms |
11864 KB |
Output is correct |
16 |
Correct |
2 ms |
11868 KB |
Output is correct |
17 |
Incorrect |
2 ms |
11868 KB |
Output isn't correct |
18 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
11868 KB |
Output is correct |
2 |
Correct |
2 ms |
11868 KB |
Output is correct |
3 |
Correct |
2 ms |
11868 KB |
Output is correct |
4 |
Correct |
2 ms |
11868 KB |
Output is correct |
5 |
Correct |
2 ms |
11840 KB |
Output is correct |
6 |
Correct |
2 ms |
11864 KB |
Output is correct |
7 |
Correct |
2 ms |
11876 KB |
Output is correct |
8 |
Correct |
2 ms |
11864 KB |
Output is correct |
9 |
Correct |
2 ms |
11864 KB |
Output is correct |
10 |
Correct |
2 ms |
11864 KB |
Output is correct |
11 |
Correct |
2 ms |
11868 KB |
Output is correct |
12 |
Correct |
2 ms |
11868 KB |
Output is correct |
13 |
Correct |
2 ms |
11864 KB |
Output is correct |
14 |
Correct |
2 ms |
11864 KB |
Output is correct |
15 |
Correct |
2 ms |
11864 KB |
Output is correct |
16 |
Correct |
2 ms |
11868 KB |
Output is correct |
17 |
Incorrect |
2 ms |
11868 KB |
Output isn't correct |
18 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
11868 KB |
Output is correct |
2 |
Correct |
2 ms |
11868 KB |
Output is correct |
3 |
Correct |
2 ms |
11868 KB |
Output is correct |
4 |
Correct |
2 ms |
11868 KB |
Output is correct |
5 |
Correct |
2 ms |
11840 KB |
Output is correct |
6 |
Correct |
2 ms |
11864 KB |
Output is correct |
7 |
Correct |
2 ms |
11876 KB |
Output is correct |
8 |
Correct |
2 ms |
11864 KB |
Output is correct |
9 |
Correct |
2 ms |
11864 KB |
Output is correct |
10 |
Correct |
2 ms |
11864 KB |
Output is correct |
11 |
Correct |
2 ms |
11868 KB |
Output is correct |
12 |
Correct |
2 ms |
11868 KB |
Output is correct |
13 |
Correct |
2 ms |
11864 KB |
Output is correct |
14 |
Correct |
2 ms |
11864 KB |
Output is correct |
15 |
Correct |
2 ms |
11864 KB |
Output is correct |
16 |
Correct |
2 ms |
11868 KB |
Output is correct |
17 |
Incorrect |
2 ms |
11868 KB |
Output isn't correct |
18 |
Halted |
0 ms |
0 KB |
- |