제출 #986103

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
986103		AlphaMale06	커다란 상품 (IOI17_prize)	C++17	96.41 / 100	45 ms	11592 KiB

prize

#include <bits/stdc++.h>

#include "prize.h"

using namespace std;
using ll = long long;

//vector<int> ask(int i);

vector<int> a[200006];
int summ = 0;

int solve(int l, int r){
    if(l+1>=r)return 0;
    int cnt = a[l][1]-a[r][1];
    if(cnt==0)return 0;
    int s = l+r>>1;
    if(a[s][0]==-1)a[s]=ask(s);
    if(a[s][0]+a[s][1]==summ)return max(solve(l, s), solve(s, r));
    if(a[s][0]+a[s][1]==0)return s;
    int R = s-1, L = s+1;
    for(int i=s-1; i>=l; i--){
        if(a[i][0]==-1)a[i]=ask(i);
        if(a[i][0]+a[i][1]==0)return i;
        if(a[i][0]+a[i][1]==summ){
            R=i;
            break;
        }
    }
    for(int i=s+1; i<=r; i++){
        if(a[i][0]==-1)a[i]=ask(i);
        if(a[i][0]+a[i][1]==0)return i;
        if(a[i][0]+a[i][1]==summ){
            L=i;
            break;
        }
    }
    return max(solve(l, R), solve(L, r));
}

int find_best(int n){
	if(n<=5000){
        for(int i=0; i<n; i++){
            vector<int> ans = ask(i);
            if(ans[0]==0 && ans[1]==0)return i;
        }
	}
	for(int i=0; i< n; i++){
        a[i].push_back(-1);
	}
    for(int i=0; i<600; i++){
        ll ind = i;
        if(a[ind][0]!=-1){
            i--;
            continue;
        }
        vector<int> ans = ask(ind);
        a[ind]=ans;
        summ=max(summ, ans[0]+ans[1]);
        if(ans[0]+ans[1]==0)return ind;
    }
    int L = 0, R = n-1;
    for(int i=0; i<n; i++){
        if(a[i][0]==-1)a[i] = ask(i);
        if(a[i][0]+a[i][1]==summ){
            L=i;
            break;
        }
        if(a[i][0]+a[i][1]==0)return i;
    }
    for(int i=n-1; i>=0; i--){
        if(a[i][0]==-1)a[i]=ask(i);
        if(a[i][0]+a[i][1]==summ){
            R=i;
            break;
        }
        if(a[i][0]+a[i][1]==0)return i;
    }
    return solve(L, R);
}

컴파일 시 표준 에러 (stderr) 메시지

prize.cpp: In function 'int solve(int, int)':
prize.cpp:17:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   17 |     int s = l+r>>1;
      |             ~^~

• Subtask 1: 20 / 20
• Subtask 2: 76.41 / 80