제출 #684455

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
684455		Chal1shkan	Bigger segments (IZhO19_segments)	C++14	27 / 100	1 ms	340 KiB

segments

# include <bits/stdc++.h>

# define pb push_back
# define ff first
# define ss second
# define nl "\n"
# define sz(x) ((int)(x).size())

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;

const ll maxn = 5e5 + 25;
const ll inf = 1e18 + 0;
const ll mod = 1e9 + 7;
const ll dx[] = {-1, 1, 0, 0};
const ll dy[] = {0, 0, -1, 1};

using namespace std;

ll n, a[maxn], pref[maxn];
pair <ll, ll> dp[maxn];

void ma1n (/* SABR */)
{
    cin >> n;
    for (ll i = 1; i <= n; ++i)
    {
        cin >> a[i];
        pref[i] = pref[i - 1] + a[i];
        dp[i].ss = -1;
    }
    dp[1].ff = 1, dp[1].ss = pref[1];
    for (ll i = 1; i <= n; ++i)
    {
        if (dp[i - 1].ff > dp[i].ff)
        {
            dp[i].ff = dp[i - 1].ff;
            dp[i].ss = dp[i - 1].ss + a[i];
        }
        ll l = i + 1, r = n, pos = -1;
        while (l <= r)
        {
            ll mid = (l + r) >> 1;
            if (pref[mid] >= dp[i].ss + pref[i])
            {
                r = mid - 1;
                pos = mid;
            }
            else
            {
                l = mid + 1;
            }
        }
        if (pos == -1) continue;
        if (dp[i].ff + 1 > dp[pos].ff)
        {
            dp[pos].ff = dp[i].ff + 1;
            dp[pos].ss = pref[pos] - pref[i];
        }
        else if (dp[i].ff + 1 == dp[pos].ff)
        {
            dp[pos].ff = dp[i].ff + 1;
            if (dp[pos].ss == -1) dp[pos].ss = pref[pos] - pref[i];
            else dp[pos].ss = min(dp[pos].ss, pref[pos] - pref[i]);
        }
    }
    cout << dp[n].ff << nl;
}

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
//  freopen("file.in", "r", stdin);
//  freopen("file.out", "w", stdout);
    int ttt = 1;
//  cin >> ttt;
    for (int test = 1; test <= ttt; ++test)
    {
//      cout << "Case " << test << ":" << ' ';
        ma1n();
    }
    return 0;
}

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