Submission #986130

#	Time	Username	Problem	Language	Result	Execution time	Memory
986130		AlphaMale06	The Big Prize (IOI17_prize)	C++17	20 / 100	53 ms	11768 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);
	}
	int L = -1, R = -1;
    for(int i=0; i<235; i++){
        a[i] = ask(i);
        summ=max(summ, a[i][0]+a[i][1]);
        if(a[i][0]+a[i][1]==0)return i;
    }
    for(int i=n-1; i>=n-235; i--){
        a[i]=ask(i);
        summ=max(summ, a[i][0]+a[i][1]);
        if(a[i][0]+a[i][1]==0)return i;
    }
    for(int i=235; i<n; i++){
        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;
        }
    }
    for(int i=n-236; i>=0; i--){
        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;
        }
    }
    return solve(L, R);
}

Compilation message (stderr)

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: 0 / 80