Submission #1246427

#	Time	Username	Problem	Language	Result	Execution time	Memory
1246427		radaiosm7	Hack (APIO25_hack)	C++20	0 / 100	8 ms	1600 KiB

hack

//chockolateman credit
#include<bits/stdc++.h>
#include <vector>
#include "hack.h"

using namespace std;

const long long S = 27777;
const long long N = 1000000000;
vector<long long> temp, xf, xs, xs1, xs2, y, di;
long long diff;

long long query_pair(int x)
{
    temp.clear();
    temp.push_back(1);
    temp.push_back(1+x);
    return collisions(temp);
}

int hack(){
    xf.clear();
    for(long long i=1; i <= S; ++i) xf.push_back(i);
    xs.clear();
    for(long long i=S*(N/2LL/S); i <= N+S; i += S) xs.push_back(i);

    while ((int)xf.size() > 1 || (int)xs.size() > 1) {
        if ((int)xf.size() > (int)xs.size()) swap(xf, xs);
        int m = (int)xs.size();
        xs1.clear();
        for (int i=0; i < m/2; ++i) xs1.push_back(xs[i]);
        xs2.clear();
        for (int i=m/2; i < m; ++i) xs2.push_back(xs[i]);

        y.clear();
        for (auto el : xf) y.push_back(el);
        for (auto el : xs1) y.push_back(el);
        if (collisions(y) != 0) xs = xs1;
        else xs = xs2;
    }

    diff = llabs(xs[0]-xf[0]);
    for (long long d=2LL; d*d <= diff; ++d) {
        if (diff % d == 0LL) {
            di.push_back(d);
            di.push_back(diff/d);
        }
    }

    di.push_back(diff);
    sort(di.begin(), di.end());
    int dsz = (int)di.size();

    for (int p=0; p < dsz; ++p) {
        vector<long long> v;
        v.push_back(1LL);
        v.push_back(di[p]+1LL);
        if (collisions(v) == 1) return di[p];
    }
}

Compilation message (stderr)

hack.cpp: In function 'int hack()':
hack.cpp:60:1: warning: control reaches end of non-void function [-Wreturn-type]
   60 | }
      | ^

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 17
• Subtask 3: 0 / 75