Submission #41862

#	Time	Username	Problem	Language	Result	Execution time	Memory
41862		rahasia	The Big Prize (IOI17_prize)	C++14	20 / 100	23 ms	2020 KiB

prize

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

#define repU(x, y) for(int i = x; i <= y; ++i)
#define mp make_pair
#define pb push_back
#define allV(x) x.begin(), x.end()
#define fi first
#define se second

typedef long long LL;
typedef vector< int > vi;
typedef vector< vi > vvi;
typedef pair< int, int > pii;
typedef vector< pii > vpii;
typedef vector< LL > vL;
typedef vector< vL > vvL;
typedef vector< bool > vb;

// GLOBAL
int SUM = -1;
// --

int foo(int le, int ri, int all) {
    if (le > ri || all == 0) return -1;

    int mid1 = (le + ri) / 2, mid2 = mid1+1, allL = 0, allR = 0;

    vi tmp = ask(mid1);
    allL = all - tmp[1];
    while (tmp[0] + tmp[1] != SUM && le <= mid1) {
        if (tmp[0] == 0 && tmp[1] == 0)
            return mid1;

        if (le > mid1-1) break;
        --mid1;
        tmp = ask(mid1);
        allL = all - tmp[1];
    }

    if (mid2 <= ri) {
        tmp = ask(mid2);
        allR = all - tmp[0];
    }

    while (tmp[0] + tmp[1] != SUM && mid2 <= ri) {
        if (tmp[0] == 0 && tmp[1] == 0)
            return mid2;

        if (mid2 + 1 > ri) break;
        ++mid2;
        tmp = ask(mid2);
    }

    int res = foo(le, mid1-1, allL);
    if (res != -1) return res;

    return foo(mid2+1, ri, allR);
}

int find_best(int n) {
    if (n <= 5000) {
        vi tmp;
        repU(0, n-1) {
            tmp = ask(i);
            if (tmp[0] == 0 && tmp[1] == 0)
                return i;
        }
        return -1;
    }
    else {
        repU(0, min(n-1, 500)) {
            vi tmp = ask(i);
            SUM = max(SUM, tmp[0] + tmp[1]);
        }

        return foo(0, n-1, SUM);
    }
}

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