Submission #1205179

#	Time	Username	Problem	Language	Result	Execution time	Memory
1205179		Khalid_Alabdullatif	Hack (APIO25_hack)	C++17	100 / 100	74 ms	2052 KiB

hack

#include "hack.h"
#include <bits/stdc++.h>
#define ll long long
#define F first
#define S second
using namespace std;
const ll N=1e6,mod=1e9+7,sq=27383;
ll coll(vector<ll>a,vector<ll>b){
	vector<ll>v;
	for(auto i:a)
		v.push_back(i);
	for(auto i:b)
		v.push_back(i);
    
	return collisions(v);
}
int hack(){
    vector<ll> a,b;
    for(int i=1;i<=sq;i++)
    	a.push_back(i);
    for(int i=sq*(5e8/sq);i<=1e9+sq;i+=sq)
    	b.push_back(i);
    
    while(a.size()>1 || b.size()>1){
    	if(a.size()>b.size()){
    		vector<ll>f,s;
    		int idx;
            //cout<<"F: ";
    		for(idx=0;idx<a.size()/2;idx++){
    			f.push_back(a[idx]);
                //cout<<a[idx]<<" ";
            }
    		//cout<<endl<<"S: ";
    		for(;idx<a.size();idx++){
    			s.push_back(a[idx]);
                //cout<<a[idx]<<" ";
            }
            //cout<<endl;
    		if(coll(s,b))
    			a=s;
    		else
    			a=f;
    	}
    	else{
    		vector<ll>f,s;
    		int idx;
            //cout<<"F: ";
    		for(idx=0;idx<b.size()/2;idx++){
    			f.push_back(b[idx]);
                //cout<<b[idx]<<" ";
            }
    		//cout<<endl<<"S: ";
    		for(;idx<b.size();idx++){
                s.push_back(b[idx]);
                //cout<<b[idx]<<" ";
            }
            //cout<<endl;
    		if(coll(a,f))
    			b=f;
    		else
    			b=s;
    	}
    }
    //cout<<a[0]<<" "<<b[0]<<endl;
    //cout<<coll(a,b);
    ll m=b[0]-a[0],m1=m;
    set<int>prime;

    for (int i=2;i*i<=1e9;i++){
    	while(m1%i==0){
    		m1/=i;
    		prime.insert(i);
    	}
    }
    if(m1!=1)
    	prime.insert(m1);
    for(auto i:prime){
    	while(m%i==0 && collisions({1,m/i+1})){
    		m/=i;
        }
    }

    return m;
}

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