제출 #906074

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
906074		nightfal	커다란 상품 (IOI17_prize)	C++14	100 / 100	25 ms	600 KiB

prize

//#include "prize.h"
#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

static const int max_q = 10000;
static int n;
static int query_count = 0;
static vector<int> g;
static vector<vector<int> > rank_count;

int find_best(int n);
std::vector<int> ask(int i);

int subtask1(int n){
    int start=0, end=n-1;
    while (start<end) {
        int mid = (start+end)/2;
        vector<int> ans = ask(mid);
        if (!ans[0] && !ans[1]) return mid;
        else if (!ans[0]) start=mid+1;
        else end = mid-1;
    }
    return start;
}

int bSearch97(int start, int end, std::vector<int> sAns, std::vector<int> eAns, int maxVal) {

    if (sAns[0]+sAns[1]==0) return start;
    if (eAns[0]+eAns[1]==0) return end;
    
    while(start + 1 < end && sAns[0]+sAns[1]!=maxVal) {
        sAns = ask(++start); 
        if (sAns[0]+sAns[1]==0) return start;
    }
    while(start + 1 < end && eAns[0]+eAns[1]!=maxVal) {
        eAns = ask(--end);
        if (eAns[0]+eAns[1]==0) return end;
    }

    if(start+1==end || sAns[0]==eAns[0]) return -1;

    int mid=(start+end+1)/2;
    vector<int> midAns = ask(mid);
    int result = bSearch97(start,mid,sAns,midAns,maxVal);
    if (result != -1) return result;
    return bSearch97(mid,end,midAns,eAns,maxVal);
}

int score97(int n) {
    int m = min(500,n), maxVal=0;
    vector<int> ans;
	for(int i=0; i<m; i++) {
        ans = ask(i);
        int sum = ans[0]+ans[1];
        if(sum==0) return i;
        if (maxVal<sum) maxVal=sum;
    }
	return bSearch97(0,n-1,ask(0),ask(n-1),maxVal);
}

int bSearch(int start, int end, std::vector<int> sAns, std::vector<int> eAns) {

    if (sAns[0]+sAns[1]==0) return start;
    if (eAns[0]+eAns[1]==0) return end;
    
    while(start + 1 < end && sAns[0]+sAns[1]!=eAns[0]+eAns[1]) {
        if (sAns[0]+sAns[1] < eAns[0]+eAns[1]) {
            sAns = ask(++start); 
            if (sAns[0]+sAns[1]==0) return start;
        }
        else {
            eAns = ask(--end);
            if (eAns[0]+eAns[1]==0) return end;
        }
    }
    if(start+1==end || sAns[0]==eAns[0]) return -1;

    int mid=(start+end+1)/2;
    vector<int> midAns = ask(mid);
    int result = bSearch(start,mid,sAns,midAns);
    if (result != -1) return result;
    return bSearch(mid,end,midAns,eAns);
}

int fulltask(int n) { 
	return bSearch(0,n-1,ask(0),ask(n-1));
}

int find_best(int n) {
    return fulltask(n);
    // return score97(n);
}

컴파일 시 표준 에러 (stderr) 메시지

prize.cpp:10:12: warning: 'query_count' defined but not used [-Wunused-variable]
   10 | static int query_count = 0;
      |            ^~~~~~~~~~~
prize.cpp:9:12: warning: 'n' defined but not used [-Wunused-variable]
    9 | static int n;
      |            ^

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