Submission #295917

#	Time	Username	Problem	Language	Result	Execution time	Memory
295917		Aldas25	The Big Prize (IOI17_prize)	C++14	90 / 100	105 ms	5628 KiB

prize

#include "prize.h"
#include <bits/stdc++.h>

using namespace std;

#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr)
#define FOR(i, a, b) for(int i = (a); i <= (b); i++)
#define REP(n) FOR(O, 1, (n))
#define pb push_back
#define f first
#define s second
typedef long double ld;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<int, pii> piii;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<ll> vl;
typedef vector<piii> viii;
mt19937 rng (chrono::steady_clock::now().time_since_epoch().count());

const int MAXN = 200100;

bool ch[MAXN];
vi got[MAXN];

vi get (int id) {
    if(!ch[id]) {
        ch[id] = true;
        got[id] = ask(id);
    }
    return got[id];
}


int brute_find (int n){
    FOR(i, 0, n-1) {
        vi a = get(i);
        if (a[0] + a[1] == 0) return i;
    }
    return 0;
}

int find_best(int n) {
    if (n <= 5000) return brute_find(n);
    int bg = 0; /// bg = 0
    int m = 1000; /// m = 1000
    FOR(i, 0, m-1) {
        vi a = get(i);
        if (a[0] + a[1] == 0) return i;
        bg = max(bg, a[0]+a[1]);
    }

    FOR(i, 0, n-1) {
        vi a = get(i);
        if (a[0] + a[1] == 0) return i;
        if (a[0] + a[1] == bg) {
            int le = i, ri = n-1;
            while (le < ri) {
                int mid = (le+ri+1)/2;
                vi a2 = get(mid);
                while (a2[0] + a2[1] != bg) {
                    if (a2[0] + a2[1] == 0) return mid;
                    mid--;
                    ri = mid;
                    a2 = get(mid);
                }
                if (a2[0] != a[0]) ri = mid-1;
                else le = mid;

            }
            i = le;
        }
    }

    return 0;
}

• Subtask 1: 20 / 20
• Subtask 2: 70 / 80