1055C - Lucky Days(数论)

题解

// Problem: C. Lucky Days
// Contest: Codeforces - Mail.Ru Cup 2018 Round 2
// URL: https://codeforces.com/problemset/problem/1055/C
// Memory Limit: 256 MB
// Time Limit: 1000 ms
// 
// Powered by CP Editor (https://cpeditor.org)

#include<bits/stdc++.h>
using namespace std;

int main(){
	int la,ra,ta,lb,rb,tb;
	cin>>la>>ra>>ta>>lb>>rb>>tb;
	int num=__gcd(ta,tb);
	if(la<lb) swap(la,lb),swap(ra,rb);
	int sum=la-lb;
	lb=lb+sum/num*num;
	rb=rb+sum/num*num;
	int ans=max(0,min(rb,ra)-max(la-1,lb-1));
	lb+=num;rb+=num;
	ans=max(ans,min(ra,rb)-max(la-1,lb-1));
	cout<<ans<<endl;
	return 0;
}