Submission #793226

#	Time	Username	Problem	Language	Result	Execution time	Memory
793226		alvingogo	Aliens (IOI16_aliens)	C++14	4 / 100	1 ms	300 KiB

aliens

#include "aliens.h"
#include <bits/stdc++.h>
#pragma GCC optimize("Ofast")
#define AquA cin.tie(0);ios_base::sync_with_stdio(0);
#define fs first
#define sc second
#define p_q priority_queue
#define sz(a) ((int)(a.size()))
using namespace std;

typedef long long ll;
typedef pair<ll,ll> pll;
vector<ll> v;
int n;
bool check1(pll a,pll b,int c){
    return a.fs*c+a.sc>b.fs*c+b.sc;
}
bool check2(pll a,pll b,pll c){
    return (b.sc-a.sc)*(b.fs-c.fs)<=(b.sc-c.sc)*(b.fs-a.fs);
}
ll get(ll p,bool x){
    vector<pair<pll,int> > dq;
    vector<pll> dp(n);
    int l=0;
    dq.push_back({{1-v[0],(1-v[0])*(1-v[0])},0});
    for(int i=0;i<n;i++){
        while(sz(dq)-l>1 && check1(dq[l].fs,dq[l+1].fs,2*i)){
            l++;
        }
        dp[i].fs=2ll*i*dq[l].fs.fs+dq[l].fs.sc+1ll*i*i+p;
        dp[i].sc=dq[l].sc+1;
        int xf=0;
        if(i>=v[i+1]){
            xf=-(i-v[i+1]+1)*(i-v[i+1]+1);
        }
        ll a=(1-v[i+1]),b=dp[i].fs+(1ll*(1-v[i+1])*(1-v[i+1]))+xf;
        while(sz(dq)-l>1 && check2(dq[sz(dq)-1].fs,dq[sz(dq)-2].fs,{a,b})){
            dq.pop_back();
        }
        dq.push_back({{a,b},dp[i].sc});
    }
    if(x==0){
        return dp[n-1].sc;
    }
    else{
        return dp[n-1].fs;
    }
}
ll take_photos(int N, int M, int k, vector<int> R, vector<int> C) {
    n=M;
    int m=N;
    v.resize(n+1,n);
    for(int i=0;i<m;i++){
        if(R[i]<C[i]){
            swap(R[i],C[i]);
        }
        v[R[i]]=min(v[R[i]],(ll)C[i]);
    }
    for(int i=n-2;i>=0;i--){
        v[i]=min(v[i],v[i+1]);
    }
    ll l=0,r=2e14;
    while(r>l){
        ll mid=(l+r)/2;
        if(get(mid,0)<=k){
            r=mid;
        }
        else{
            l=mid+1;
        }
    }
    return get(l,1)+l*k;
}

• Subtask 1: 4 / 4
• Subtask 2: 0 / 12
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 0 / 40