Submission #1297169

#	Time	Username	Problem	Language	Result	Execution time	Memory
1297169		nvc2k8	Bigger segments (IZhO19_segments)	C++20	100 / 100	112 ms	45396 KiB

segments

#include <bits/stdc++.h>
#define TASK "fgfgf"
#define endl mmm
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define BIT(i,x) (((i)>>(x))&1)
#define FOR(i,a,b) for(int i = (a); i<=(b); i++)
#define FORD(i,a,b) for(int i = (a); i>=(b); i--)
#define all(C) (C).begin(), (C).end()
using namespace std;
using ll = long long;
using pii = pair<int,int>;
const int INT_LIM = 2147483647;
const ll LL_LIM = 9223372036854775807;
template <typename X> bool minimize(X &x, const X &y) {if (x>y){x = y; return true;}return false;}
template <typename X> bool maximize(X &x, const X &y) {if (x<y){x = y; return true;}return false;}
///------------------------------------------///
int n;
ll a[500005];
ll pf[500005];

void inp()
{
    cin >> n;
    FOR(i, 1, n)
    {
        cin >> a[i];
        pf[i] = pf[i-1]+a[i];
    }
}

struct cmp{
    bool operator() (const pii &x, const pii &y)
    {
        if (x.fi!=y.fi) return x.fi>y.fi;
        return x.se<y.se;
    }
};

int f[500005];
ll g[500005];
vector<pii> sw[500005];
priority_queue<pii, vector<pii>, cmp> q;

void solve()
{
    FOR(i, 1, n)
    {
        for (auto kk:sw[i])
        {
            q.push(kk);
        }
        f[i] = i-1; g[i] = pf[i];
        if (!q.empty())
        {
            pii u = q.top();
            pair<int,ll> alt = mp(u.fi+i, pf[i]-pf[u.se]);
            if (minimize(f[i], alt.fi)) g[i] = alt.se;
            else if (f[i]==alt.fi) minimize(g[i], alt.se);
        }

        int l = i+1, r = n, ret = n+1;
        while (l<=r)
        {
            int mid = (l+r)>>1;
            if (g[i]<=pf[mid]-pf[i])
            {
                ret = mid;
                r = mid-1;
            }
            else l = mid+1;
        }
        sw[ret].pb(mp(f[i]-i-1, i));
    }
    cout << n-f[n];
}

signed main()
{
    ///--------------------------///
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    if (fopen(TASK".INP","r")!=NULL)
    {
        freopen(TASK".INP","r",stdin);
        freopen(TASK".OUT","w",stdout);
    }
    ///--------------------------///

    int NTEST = 1;
    bool multitest = 0;
    if (multitest) cin >> NTEST;

    while (NTEST--)
    {
        inp();
        solve();
    }

    return 0;
}

///------------------------------------------///

Compilation message (stderr)

segments.cpp: In function 'int main()':
segments.cpp:86:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   86 |         freopen(TASK".INP","r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
segments.cpp:87:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   87 |         freopen(TASK".OUT","w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

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