Submission #1078833

#	Time	Username	Problem	Language	Result	Execution time	Memory
1078833		vnm06	Bulldozer (JOI17_bulldozer)	C++14	75 / 100	1289 ms	132120 KiB

bulldozer

#include<bits/stdc++.h>
#define endl '\n'

using namespace std;

struct Point
{
    long long x, y, val, nom;
    Point() {}
    Point(long long a, long long b, long long c, long long d)
    {
        x=a;
        y=b;
        val=c;
        nom=d;
    }
};

bool operator<(Point p, Point q)
{
    if(p.x==q.x) return p.y>q.y;
    return p.x<q.x;
}

struct Line
{
    Point a, b;
    Line() {}
    Line(Point p, Point q)
    {
        a.x=p.x;
        a.y=p.y;
        a.val=p.val;
        a.nom=p.nom;
        b.x=q.x;
        b.y=q.y;
        b.val=q.val;
        b.nom=q.nom;
    }
};

bool cmp(Line p, Line q)
{
    if(p.a.x==p.b.x && q.a.x==q.b.x) return (p.b.y-p.a.y) > (q.b.y-q.a.y);
    if(p.a.x==p.b.x) return 1;
    if(q.a.x==q.b.x) return 0;
    return ((p.b.y-p.a.y) * (q.b.x-q.a.x)) < ((q.b.y-q.a.y) * (p.b.x-p.a.x));
}

bool operator==(Line p, Line q)
{
    return ((p.b.y-p.a.y) * (q.b.x-q.a.x)) == ((q.b.y-q.a.y) * (p.b.x-p.a.x));
}

long long n, brl=0;
long long pos[2005];
Point P[2005];

vector<Line> L;

long long ans=0;
long long A[2005];

void solve()
{
    long long res=0;
    for(long long i=0; i<n; i++)
    {
        res+=A[i];
        if(res<0) res=0;
        if(res>ans) ans=res;
    }
}

long long sum[8005], pref[8005], suf[8005], mx[8005];

void update(int v, int le, int ri, int id, long long val)
{
    //cout<<v<<' '<<le<<" "<<ri<<endl;
    if(le==ri)
    {
        sum[v]=val;
        pref[v]=max(sum[v], 0LL);
        suf[v]=max(sum[v], 0LL);
        mx[v]=max(sum[v], 0LL);
        return;
    }
    int mid=(le+ri)/2;
    if(id<=mid) update(2*v, le, mid, id, val);
    else update(2*v+1, mid+1, ri, id, val);

    sum[v]=sum[2*v]+sum[2*v+1];
    pref[v]=max(pref[2*v], sum[2*v]+pref[2*v+1]);
    suf[v]=max(suf[2*v+1], suf[2*v]+sum[2*v+1]);
    mx[v]=max(max(mx[2*v], mx[2*v+1]), suf[2*v]+pref[2*v+1]);
}


int main()
{
   // ios::sync_with_stdio(0);
   // cin.tie(0);
   // cout.tie(0);

    cin>>n;
    for(long long i=0; i<n; i++) cin>>P[i].x>>P[i].y>>P[i].val;
    sort(P, P+n);
    for(long long i=0; i<n; i++) P[i].nom=i;
    for(long long i=0; i<n; i++)
    {
        A[i]=P[i].val;
        pos[i]=i;
        for(long long j=i+1; j<n; j++)
        {
            L.push_back(Line(P[i], P[j]));
            ///cout<<L[brl].a.x<<" "<<L[brl].a.y<<" "<<L[brl].b.x<<" "<<L[brl].b.y<<"\n";
            brl++;
        }
    }
    ///cout<<brl<<endl;
    sort(L.begin(), L.end(), cmp);

    for(int i=0; i<n; i++)
    {
        update(1, 0, n-1, i, A[i]);
    }

    for(long long i=0; i<brl; i++)
    {
       /// cout<<L[i].a.x<<" "<<L[i].a.y<<" "<<L[i].b.x<<" "<<L[i].b.y<<endl;
        if(i==0 || !(L[i]==L[i-1])) ans=max(ans, mx[1]); ///cout<<i<<endl;}
        Point t1=L[i].a, t2=L[i].b;
        update(1, 0, n-1, pos[t2.nom], A[pos[t1.nom]]);
        update(1, 0, n-1, pos[t1.nom], A[pos[t2.nom]]);
        swap(A[pos[t1.nom]], A[pos[t2.nom]]);
        swap(pos[t1.nom], pos[t2.nom]);
    }
    ans=max(ans, mx[1]);
    cout<<ans<<endl;
    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 20 / 20
• Subtask 3: 35 / 35
• Subtask 4: 20 / 20
• Subtask 5: 0 / 20