Submission #300859

#	Time	Username	Problem	Language	Result	Execution time	Memory
300859		milisav	Carnival Tickets (IOI20_tickets)	C++14	100 / 100	2004 ms	84132 KiB

tickets

#include "tickets.h"
#include<bits/stdc++.h>
#pragma GCC optimize("O3")
#define maxn 2000
using namespace std;
priority_queue<pair<int,int>> pq;
vector<int> fr[maxn];
vector<int> bk[maxn];
int tt[maxn];
//vector<vector<int>> s;
long long find_maximum(int k,vector<vector<int>> x) {
	int n = x.size();
	int m = x[0].size();
    vector<vector<int>> s;
    for(int i=0;i<n;i++) {
        vector<int> row;
        for(int j=0;j<m;j++) row.push_back(-1);
        s.push_back(row);
    }
	for(int i=0;i<n;i++) for(int j=0;j<k;j++) pq.push({x[i][m-j-1]+x[i][k-1-j],i});
	long long ans=0;
	for(int i=0;i<n;i++) for(int j=0;j<k;j++) ans-=x[i][j];
	for(int i=0;i<n*k/2;i++) {
        ans+=pq.top().first;
        tt[pq.top().second]++;
        pq.pop();
	}
    for(int i=0;i<n;i++) {
        for(int j=0;j<k-tt[i];j++) fr[i].push_back(k-tt[i]-1-j);
        for(int j=0;j<tt[i];j++) bk[i].push_back(m-tt[i]+j);
    }
    //return ans;
    for(int d=0;d<k;d++) {
        long long l=0;
        long long r=1e9;
        while(l<=r) {
            long long t=(l+r)/2;
            int p=0,q=0;
            int dir=0;
            for(int i=0;i<n;i++) {
                //cout<<fr[i].size()<<" "<<bk[i].size()<<endl;
                if(fr[i].empty() && x[i][bk[i].back()]<t) {
                    dir=-1;
                    break;
                }
                if(bk[i].empty() && x[i][fr[i].back()]>t) {
                    dir=1;
                    break;
                }
                if(!fr[i].empty() && x[i][fr[i].back()]<=t) p++;
                if(!bk[i].empty() && x[i][bk[i].back()]>=t) q++;
            }
            if(dir!=0) {
                if(dir==-1) r=t-1;
                else l=t+1;
                continue;
            }
            //cout<<p<<" "<<q<<" "<<l<<" "<<r<<" "<<t<<endl;
            //assert(p>=n/2 || q>=n/2);
            if(p>=n/2 && q>=n/2) {
                p=0;
                q=0;
                for(int i=0;i<n;i++) {
                    if((!fr[i].empty() && x[i][fr[i].back()]<=t) && !(!bk[i].empty() && x[i][bk[i].back()]>=t)) {
                        s[i][fr[i].back()]=d;
                        p++;
                    }
                    if(!(!fr[i].empty() && x[i][fr[i].back()]<=t) && (!bk[i].empty() && x[i][bk[i].back()]>=t)) {
                        s[i][bk[i].back()]=d;
                        q++;
                    }
                }
                for(int i=0;i<n;i++) {
                    if((!fr[i].empty() && x[i][fr[i].back()]<=t) && (!bk[i].empty() && x[i][bk[i].back()]>=t)) {
                        if(p<n/2) {
                            s[i][fr[i].back()]=d;
                            fr[i].pop_back();
                            p++;
                        }
                        else {
                            s[i][bk[i].back()]=d;
                            bk[i].pop_back();
                            q++;
                        }
                    }
                    else {
                        if((!fr[i].empty() && x[i][fr[i].back()]<=t) && !(!bk[i].empty() && x[i][bk[i].back()]>=t)) fr[i].pop_back();
                        if(!(!fr[i].empty() && x[i][fr[i].back()]<=t) && (!bk[i].empty() && x[i][bk[i].back()]>=t)) bk[i].pop_back();
                    }
                }
                break;
            }
            if(p<n/2) l=t+1;
            if(q<n/2) r=t-1;
        }
    }
	allocate_tickets(s);
	return ans;
}

/*int main() {
    int n,m,k;
    vector<vector<int>> x;
    scanf("%d %d %d", &n, &m, &k);
    x.resize(n);
    for (int i = 0; i < n; i++) {
        x[i].resize(m);
        for (int j=0; j < m; j++) {
            scanf("%d", &x[i][j]);
        }
    }

    long long answer = find_maximum(k, x);
    printf("%lld\n", answer);
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (j) printf(" ");
            printf("%d", s[i][j]);
        }
        printf("\n");
    }
    return 0;
}*/

• Subtask 1: 11 / 11
• Subtask 2: 16 / 16
• Subtask 3: 14 / 14
• Subtask 4: 14 / 14
• Subtask 5: 12 / 12
• Subtask 6: 23 / 23
• Subtask 7: 10 / 10