Even or odd: three player
APL (34 30)

(1⍳⍨+/∘.=⍨2|⎕)⊃'ABC',⊂'no one'


Explanation:


2|⎕: read a line of input, take the mod-2 of each number (giving a list, i.e. 1 0 1)
∘.=⍨: compare each element in the vector to each element in the vector, giving a matrix
+/: sum the rows of the matrix, giving for each element how many elements it was equal to. If there were two the same and one different, we now have a vector like 2 1 2 where the 1 denotes who was different. If they were all the same, we get 3 3 3.
1⍳⍨: find the position of the 1. If there is no 1, this returns one more than the length of the vector, in this case 4.
⊃'ABC',⊂'no one': display the string at the given index.