Submission #994835

#	Time	Username	Problem	Language	Result	Execution time	Memory
994835		salmon	Portal (BOI24_portal)	C++14	40 / 100	24 ms	2636 KiB

Main

#include <bits/stdc++.h>
using namespace std;
 
int N;
long long int x,y;
long long int b,d;
long long int b1,d1;
long long int h1,h2;
bool flag = true;
bool floog = true;
vector<pair<long long int,long long int>> v;
long long int num = 0;

mt19937 rng(chrono::high_resolution_clock::now().time_since_epoch().count());

pair<long long int, long long int> gbcd(pair<long long int, long long int> ii1, pair<long long int, long long int> ii2){
	if(ii1.first > ii2.first) swap(ii1,ii2);
	if(ii1.first == 0){
		num = __gcd(num,ii1.second);
		return ii2;
	}
	return gbcd({ii2.first % ii1.first, ii2.second - ii2.first / ii1.first * ii1.second },  ii1);
}
 
int main(){
	long long int fum = 0;
	
	scanf(" %d",&N);
	
	scanf(" %lld",&x);
	scanf(" %lld",&y);
	
	b = 0;
	d = 0;
	
	for(int i = 0; i < N - 1; i++){
		scanf(" %lld",&h1);
		scanf(" %lld",&h2);
		
		h1 -= x;
		h2 -= y;
		
		if(h1 == 0 && h2 == 0) continue;
		
		flag &= (h1==0);
		floog &= (h2==0);
		
		if(i == 0){
			
			if(h1 != 0){
				h2 *= (h1)/abs(h1);
				h1 = abs(h1);
			}

			b = h1;
			d = h2;
			
		}
		else v.push_back({h1,h2});
	}
	
	
	

	if(flag || floog){
		printf("%d",-1);
		return 0;
	}
 
	for(pair<long long int,long long int> ii : v){
		h1 = ii.first;
		h2 = ii.second;

		if(h1 != 0){
			
			h2 *= (h1)/abs(h1);
			h1 = abs(h1);
			
			long long int c = __gcd(h1,b);
			
			pair<long long int, long long int> ii = gbcd({b,d},{h1,h2});
			
			b = ii.first;
			d = ii.second;
		}
		else{
			num = __gcd(num, h2);
		}

		
		fum = b;
	}
	//printf("%lld\n",num);
	if(fum == 0 || num == 0) printf("%d",-1);
	else{
		printf("%lld",abs((long long int)num * fum));
	}
	
	
}
/*
5
0 0
2 1000000
1000007 1000005
1000003 1000005
1000007 1000001
 */

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:79:18: warning: unused variable 'c' [-Wunused-variable]
   79 |    long long int c = __gcd(h1,b);
      |                  ^
Main.cpp:28:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   28 |  scanf(" %d",&N);
      |  ~~~~~^~~~~~~~~~
Main.cpp:30:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |  scanf(" %lld",&x);
      |  ~~~~~^~~~~~~~~~~~
Main.cpp:31:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   31 |  scanf(" %lld",&y);
      |  ~~~~~^~~~~~~~~~~~
Main.cpp:37:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |   scanf(" %lld",&h1);
      |   ~~~~~^~~~~~~~~~~~~
Main.cpp:38:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |   scanf(" %lld",&h2);
      |   ~~~~~^~~~~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 29 / 29
• Subtask 5: 0 / 15
• Subtask 6: 0 / 35