Bessie gives FJ the expression (B+E+S+S+I+E)(G+O+E+S)(M+O+O), containing the seven variables B,E,S,I,G,O,M (the "O" is a variable, not a zero). For each variable, she gives FJ a list of up to 20 integer values the variable can possibly take. She asks FJ to count the number of different ways he can assign values to the variables so the entire expression evaluates to an even number.

Line 1: an integer N. The next N lines each contain a variable and a possible value for that variable. Each variable appears at least once and at most 20 times; no possible value is listed more than once for the same variable. All possible values are in the range -300 to 300.

A single integer giving the number of ways FJ can assign values to variables so the expression evaluates to an even result.

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출처 올림피아드 > USACO > 2014-2015 > US Open > Bronze