Submission #102068

#	Time	Username	Problem	Language	Result	Execution time	Memory
102068		tim25871014	The Big Prize (IOI17_prize)	C++17	20 / 100	54 ms	22392 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>
using namespace std;

int find_best(int n){

    vector<int> mem[200010];
    for(int i=0;i<200010;i++){
        mem[i].push_back(-1);
        mem[i].push_back(-1);
    }

    int loli=0;
    for(int i=0;i<(int)min(500,n);i++){
        vector<int> val=ask(i);
        loli=max(loli,val[0]+val[1]);
    }

    for(int i=0;i<n;i++){
        vector<int> val;
        if(mem[i][0]==-1) val=mem[i]=ask(i);
        else val=mem[i];

        if(val[0]+val[1]==0) return i;
        if(val[0]+val[1]==loli){

            int lb=i,ub=n;
            while(ub-lb>1){
                int mid=ub+lb>>1;
                vector<int> ser;
                if(mem[mid][0]==-1) ser=mem[mid]=ask(mid);
                if(val[0]==ser[0] && ser[0]+ser[1]==loli)
                    lb=mid;
                else ub=mid;
            }
            i=lb;
        }
    }
}

Compilation message (stderr)

prize.cpp: In function 'int find_best(int)':
prize.cpp:29:27: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
                 int mid=ub+lb>>1;
                         ~~^~~
prize.cpp:39:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^

• Subtask 1: 20 / 20
• Subtask 2: 0 / 80