void main()
{
	struct tushu
	{
		int num;
		char zuozhe[27];
	}ts[999];

	int i,j,n,k,temp;
	int count[26]={0};

	scanf("%d",&n);
	for(i=0;i<n;i++)
	{
		scanf("%d %s",&ts[i].num,ts[i].zuozhe);
		for(j=0;ts[i].zuozhe[j]!='\0';j++)
		{count[ts[i].zuozhe[j]-65]++;}
	}
	temp=count[0];
	k=0;
	for(i=0;i<26;i++)
	{
		if(count[i]>temp){k=i;temp=count[i];}
	}
	printf("%c\n",k+65);
	printf("%d\n",count[k]);
	for(i=0;i<n;i++)
	{
		for(j=0;ts[i].zuozhe[j]!='\0';j++)
		{
			if(ts[i].zuozhe[j]==k+65)
			{
				printf("%d\n",ts[i].num);
				break;
			}
		}
	}
}
