#include<iostream>
#include<algorithm>
using namespace std;
int D[7];
main()
{
	for(int i=0;i<7;i++)cin>>D[i];
	sort(D,D+7);
	do{
		bool flag=true;
		for(int i=1;i<6;i++)
		{
			flag&=D[i-1]<D[i+1]&&(D[i]<D[i-1]&&D[i]<D[i+1]||D[i]>D[i-1]&&D[i]>D[i+1]);
		}
		if(flag)
		{
			cout<<"YES"<<endl;
			return 0;
		}
	}while(next_permutation(D,D+7));
	cout<<"NO"<<endl;
}