Fred's Lotto Tickets

Fred likes to play the lotto. Whenever he does, he buys lots of tickets. Each ticket has 6 unique numbers in the range from 1 to 49, inclusive. Fred likes to ``Cover all his bases." By that, he means that he likes for each set of lottery tickets to contain every number from 1 to 49, at least once, on some ticket. Write a program to help Fred see of his tickets ``Cover all the bases."

The input file consists of a number of test cases. Each case starts with an integer N ( 1<=N<=100 ), indicating the number of tickets Fred has purchased. On the next N lines are the tickets, one per line. Each ticket will have exactly 6 integers, and all of them will be in the range from 1 to 49 inclusive. No ticket will have duplicate numbers, but the numbers on a ticket may appear in any order. The input ends with a line containing only a `0'.

Print a list of responses for the input sets, one per line. Print the word `Yes' if every number from 1 to 49 inclusive appears in some lottery ticket in the set, and `No' otherwise. Print these words exactly as they are shown. Do not print any blank lines between outputs.

1
1 2 3 4 5 6
9
1 2 3 4 5 6
10 9 8 7 12 11
13 14 15 16 17 18
19 20 21 22 23 24
25 26 27 28 29 30
31 32 33 34 35 36
37 38 39 40 41 42
43 44 45 46 47 48
49 19 34 27 25 13
0

No
Yes

2008 ACM-ICPC Southeast USA Regional