| # | Time | Username | Problem | Language | Result | Execution time | Memory |
|---|---|---|---|---|---|---|---|
| 520617 | Vimmer | Cigle (COI21_cigle) | C++14 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define in(x) freopen(x, "r", stdin)
#define out(x) freopen(x, "w", stdout)
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("-O3")
#define F first
#define S second
#define PB push_back
#define M ll(1e9 + 7)
#define sz(x) (ll)x.size()
#define N 1000500
#define pri(x) cout << x << endl
#define endl '\n'
#define all(x) (x).begin(), (x).end()
#define _ << " " <<
using namespace std;
//typedef tree <ll, null_type, less_equal <ll> , rb_tree_tag, tree_order_statistics_node_update> ordered_set;
//using namespace __gnu_pbds;
typedef long long ll;
typedef long double ld;
typedef short int si;
typedef unsigned long long ull;
si f[5001][5001][2];
vector <int> was[5001];
int pr[5001];
si now[5001][5001][2];
int main()
{
istream::sync_with_stdio(0); ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
memset(f, -1, sizeof f);
int n;
cin >> n;
int a[n], ans = 0;
for (int i = 0; i < n; i++)
cin >> a[i];
for (int i = 0; i < n; i++)
{
pr[i] = a[i];
if (i)
pr[i] += pr[i - 1];
}
for (int l = 0; l < n; l++)
{
int sum = 0;
for (int r = l; r < n; r++)
{
sum += a[r];
int L = r + 1, R = n - 1;
while (L < R)
{
int md = (L + R) >> 1;
if (pr[md] - pr[r] >= sum)
R = md;
else L = md + 1;
}
if (pr[L] - pr[r] == sum)
{
was[r].PB(L);
}
}
}
for (int i = 0; i < n; i++)
sort(all(was[i]));
memset(now, -1, sizeof now);
for (int i = 0; i < n; i++)
f[0][i][0] = 0;
for (int r = 0; r < n; r++)
for (int l = 0; l <= r; l++)
for (int t = 0; t < 2; t++)
{
if (r)
now[l][r][t] = max(now[l][r][t], now[l][r - 1][t]);
f[l][r][t] = max(f[l][r][t], now[l][r][t]);
if (f[l][r][t] != -1)
{
int kl = f[l][r][t];
int sm = pr[r], cur = 0;
if (l)
sm -= pr[l - 1];
int i = 0, bn = 0;
for (int nw = r + 1; nw < n; nw++)
{
cur += a[nw];
if (bn)
{
kl++;
bn = 0;
}
while (i < sz(was[r]) && was[r][i] == nw)
{
bn = 1;
i++;
}
f[r + 1][nw][t ^ 1] = max(f[r + 1][nw][t ^ 1], kl);
ans = max(ans, kl);
if (sm <= cur)
{
now[r + 1][nw][t ^ 1] = max(now[r + 1][nw][t ^ 1], kl);
break;
}
}
}
}
pri(ans);
}