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Problem E
Odds of Mia

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Mia is a dice game for two players. Each roll consist of two dice. Mia involves bluffing about what a player has rolled, but in this problem we focus only on its scoring rules. Unlike most other dice games, the score of a roll is not simply the sum of the dice.

Instead, a roll is scored as follows:

  • Mia (12 or 21) is always highest.

  • Next come doubles (11, 22, and so on). Ties are broken by value, with 66 being highest.

  • All remaining rolls are sorted such that the highest number comes first, which results in a two-digit number. The value of the roll is the value of that number, e.g. 3 and 4 becomes 43.

Player 1 and 2 each roll two dice. You are asked to compute the odds that player 1 will win given partial knowledge of both rolls.

Input

The input will contain multiple, different test cases. Each test case contains on a single line four symbols s0 s1 r0 r1 where s0 s1 represent the dice rolled by player 1 and r0 r1 represents the dice rolled by player 2. A ‘*’ represents that the value is not known, otherwise a digit represents the value of the dice. The input will be terminated by a line containing 4 zeros.

Output

For each test case output the odds that player 1 will win. If the odds are 0 or 1, output 0 or 1. Otherwise, output the odds in the form a/b where a and b represent the nominator and denominator of a reduced fraction (i.e., in lowest terms).

Sample Output Explanation

For * * 1 2, the best player 1 can do is tie, so his chance of winning is 0. For 1 2 * *, player 1 wins unless player 2 rolls a Mia, which happens 1 out of 18 times. For 1 2 1 3, 3 1 2 1, and 6 6 6 6 the result is already known. For * 2 2 2, player 1 wins only if she rolls a 1. For * 2 * 6, player 1 wins if he rolls a 1. If he rolls a 2, he wins with probability 5/6. He loses if he rolls a 3, 4, or 5. If he rolls a 6 he wins only if player 2 rolls a 1. Thus, his chance of winning is 1/6+5/61/6+1/61/6=12/36=1/3. When no dice are known, Player 1 will win in 615 of all possible 1296 outcomes. Player 2 will lose in 615 cases, and there are 66 possible ties. Thus, her chance of winning is 615/1296=205/432.

Sample Input 1 Sample Output 1
* * 1 2
1 2 * *
1 2 1 3
3 1 2 1
6 6 6 6
* 2 2 2
* 2 * 6
* * * *
0 0 0 0
0
17/18
1
0
0
1/6
1/3
205/432
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