#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std;
struct node{
	int score;
	int sequence;
	char name[51];
}a[310],b[310];
int cmp(node x,node y)
{
	if(x.score==y.score)
		return x.sequence<y.sequence;
	return x.score>y.score;
}
int main()
{
	int n;
	while(scanf("%d",&n)!=EOF)
	{
		memset(a,0,sizeof(a));
		memset(b,0,sizeof(b));
		for(int i=0;i<n;i++)
		{
			scanf("%s %d",&a[i].name,&a[i].score);
			a[i].sequence=i;
		}
		sort(a,a+n,cmp);
		int k1=1,k2=1;
		for(int i=0;i<n;i++)
		{
			scanf("%s %d",&b[i].name,&b[i].score);
			if(strcmp(a[i].name,b[i].name)!=0)	k1=0;
			if(a[i].score!=b[i].score)	k2=0;
		}	
		if(k1+k2==2)
			printf("Right\n");
		else if(k1==0&&k2==1)/*²»خب¶¨*/ 
		{
			printf("Not Stable\n");
			for(int i=0;i<n;i++)
				printf("%s %d\n",a[i].name,a[i].score); 
		}
		else
		{
			printf("Error\n");
			for(int i=0;i<n;i++)
				printf("%s %d\n",a[i].name,a[i].score); 
		}
	}
	return 0;
}