Submission #343655

#	Time	Username	Problem	Language	Result	Execution time	Memory
343655		spike1236	Bigger segments (IZhO19_segments)	C++14	0 / 100	2 ms	492 KiB

segments

#include <bits/stdc++.h>
using namespace std;
#define pb push_back
#define mp make_pair
#define f first
#define s second
#define ll long long
#define ld long double
#define all(_v) _v.begin(), _v.end()
#define sz(_v) (int)_v.size()
#define pii pair <int, int>
#define pll pair <ll, ll>
#define veci vector <int>
#define vecll vector <ll>


const int dx[4] = {1, -1, 0, 0};
const int dy[4] = {0, 0, -1, 1};
const double PI = 3.1415926535897932384626433832795;
const double eps = 1e-9;
const int MOD1 = 1e9 + 7;
const int MOD2 = 998244353;

const int MAXN = 5e5 + 10;
int dp[MAXN];
int p[MAXN];
ll a[MAXN];
ll pref[MAXN];
int n;

void solve() {
    cin >> n;
    for(int i = 1; i <= n; ++i) cin >> a[i], pref[i] = pref[i - 1] + a[i];
    if(n > 3000) {
        cout << n;
        exit(0);
    }
    for(int i = 1; i <= n; ++i) {
        dp[i] = 1;
        for(int j = i - 1; j > 0; --j)
            if(pref[i] - pref[j] >= pref[j] - pref[p[j]] && dp[j] + 1 > dp[i])
                dp[i] = dp[j] + 1, p[i] = j;
    }
    for(int i = 1; i < n; ++i)
        assert(pref[i] + pref[i] - pref[p[i]] <= pref[i + 1] + pref[i + 1] - pref[p[i + 1]]);
    cout << dp[n];
}


int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int T = 1;
    ///cin >> T;
    while(T--) solve(), cout << '\n';
    return 0;
}

• Subtask 1: 0 / 13
• Subtask 2: 0 / 14
• Subtask 3: 0 / 10
• Subtask 4: 0 / 36
• Subtask 5: 0 / 27