Submission #292733

#	Time	Username	Problem	Language	Result	Execution time	Memory
292733		Kastanda	The Big Prize (IOI17_prize)	C++11	20 / 100	67 ms	19576 KiB

prize

// M
#include<bits/stdc++.h>
#include "prize.h"
using namespace std;
const int N = 400005;
int n, GRes, MX;
vector < int > A[N];
inline void Ask(int i)
{
        if (!A[i].size())
                A[i] = ask(i);
}
void Solve(int l, int r, int k, int le = 0, int ri = 0)
{
        //printf("%d :: %d :: %d\n", l, r, k);
        if (r <= l || k == 0)
                return ;
        if (GRes != -1)
                return ;
        if (r - l == 1)
        {
                Ask(l);
                if (A[l][0] + A[l][1] == 0)
                        GRes = l;
                return ;
        }
        int md1 = (l + r) >> 1;
        int md2 = md1;
        int cc = 0;
        while (md2 < r)
        {
                Ask(md2);
                if (A[md2][0] + A[md2][1] == 0)
                {
                        GRes = md2;
                        return ;
                }
                if (A[md2][0] + A[md2][1] == MX)
                        break;
                cc ++;
                assert(cc <= k);
                md2 ++;
        }
        if (md2 == r)
        {
                Solve(l, md1, k - cc, le, ri + cc);
                return ;
        }
        Solve(l, md1, k - cc - (A[md2][1] - ri), le, cc + A[md2][1]);
        Solve(md2 + 1, r, A[md2][1] - ri, A[md2][0], ri);
}

int find_best(int _n)
{
        n = _n;

        if (n <= 5000)
        {
                for (int i = 0; i < n; i ++)
                {
                        vector < int > TMp = ask(i);
                        if (TMp[0] + TMp[1] == 0)
                                return i;
                }
                assert(0);
        }
        int SQ = 449;
        MX = 0;
        int opt = -1;
        for (int i = 0; i < SQ; i ++)
        {
                Ask(i);
                if (A[i][0] + A[i][1] == 0)
                        return i;
                if (MX <= A[i][0] + A[i][1])
                        MX = A[i][0] + A[i][1], opt = i;
        }
        GRes = -1;
        Solve(opt + 1, n, A[opt][1]);
        return GRes;
}

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