Submission #290419

#	Time	Username	Problem	Language	Result	Execution time	Memory
290419		eohomegrownapps	Robots (IOI13_robots)	C++14	100 / 100	2959 ms	17700 KiB

robots

#include "robots.h"
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
ll w,h;

vector<pair<int,int>> coords;

struct Node{
    int s,e;
    ll sum = 0;
    ll suffmin = 0;

    Node *l, *r;

    Node(int _s, int _e){
        s=_s; e=_e;
        if (s==e){
            return;
        }
        l = new Node(s,(s+e)/2);
        r = new Node((s+e)/2+1,e);
    }

    void clear(ll mid){
        if (s==e){
            if (e!=h-1){
                sum = mid;
            } else {
                sum = 0;
            }
            suffmin = min(0LL, mid);
            return;
        }
        l->clear(mid);
        r->clear(mid);
        sum = l->sum + r->sum;
        suffmin = min(l->suffmin+r->sum,r->suffmin);
    }

    void decrement(int ind){
        int m = (s+e)/2;
        if (s==e){
            sum--;
            suffmin = min(suffmin,sum);
            return;
        }
        if (ind<=m){
            l->decrement(ind);
        } else {
            r->decrement(ind);
        }
        sum = l->sum + r->sum;
        suffmin = min(l->suffmin+r->sum,r->suffmin);
    }
};

Node *root;

bool success(ll mid){
    root->clear(mid);
    for (auto c : coords){
        ll x = c.first;
        ll y = c.second;
        root->decrement(y);
        ll numobjs = root->suffmin;
        ll val = mid*(w-1-x);
        if (val+numobjs<0){return false;}
    }
    return true;
}
 
int putaway(int lx, int ly, int n, int xpos[], int ypos[], int xtoys[], int ytoys[]) {
    sort(xpos,xpos+lx);
    sort(ypos,ypos+ly);
    for (ll i = 0; i<n; i++){
        xtoys[i]=upper_bound(xpos,xpos+lx,xtoys[i])-xpos;
        ytoys[i]=upper_bound(ypos,ypos+ly,ytoys[i])-ypos;
    }
    w=lx+1;
    h=ly+1;
    for (ll i = 0; i<n; i++){
        coords.push_back({xtoys[i],ytoys[i]});
        if (xtoys[i]==w-1&&ytoys[i]==h-1){
            return -1;
        }
    }
    sort(coords.rbegin(), coords.rend());
    ll l = 0, r = n;
    root = new Node(0,h-1);
    while (l<=r){
        ll mid = (l+r)/2;;
        if (success(mid)){
            r=mid-1;
        } else {
            l=mid+1;
        }
    }
    return l;
}

• Subtask 1: 14 / 14
• Subtask 2: 14 / 14
• Subtask 3: 25 / 25
• Subtask 4: 37 / 37
• Subtask 5: 10 / 10