Submission #1051703

#	Time	Username	Problem	Language	Result	Execution time	Memory
1051703		becaido	The Big Prize (IOI17_prize)	C++17	100 / 100	24 ms	1724 KiB

prize

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,popcnt,sse4,abm")
#include <bits/stdc++.h>
using namespace std;

#ifdef WAIMAI
#include "grader.cpp"
#else
#include "prize.h"
#endif

#ifdef WAIMAI
#define debug(HEHE...) cout << "[" << #HEHE << "] : ", dout(HEHE)
void dout() {cout << '\n';}
template<typename T, typename...U>
void dout(T t, U...u) {cout << t << (sizeof...(u) ? ", " : ""), dout(u...);}
#else
#define debug(...) 7122
#endif

#define ll long long
#define Waimai ios::sync_with_stdio(false), cin.tie(0)
#define FOR(x,a,b) for (int x = a, I = b; x <= I; x++)
#define pb emplace_back
#define F first
#define S second

const int SIZE = 2e5 + 5;

int lc[SIZE];
map<int, set<int>> mp;

int rec(int l, int r) {
    if (l > r) return -1;
    int mid = (l + r) / 2;
    auto v = ask(mid);
    if (v[0] + v[1] == 0) return mid;
    lc[mid] = v[0];
    mp[v[0] + v[1]].insert(mid);
    auto it = mp[v[0] + v[1]].find(mid);
    if (it == mp[v[0] + v[1]].begin() || lc[*prev(it)] != lc[mid]) {
        int res = rec(l, mid - 1);
        if (res != -1) return res;
    }
    if (next(it) == mp[v[0] + v[1]].end() || lc[*next(it)] != lc[mid]) {
        int res = rec(mid + 1, r);
        if (res != -1) return res;
    }
    return -1;
}

int find_best(int n) {
    mp.clear();
    return rec(0, n - 1);
}

/*
in1
8
3 2 3 1 3 3 2 3
*/

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