The following are the rules of the \(4\times 4\) Kenken above:
First, solve the puzzle, where \(K\) is a strictly positive integer.
If there is a unique value of \(K\), determine whether or not \(x + y + z + w = K\).
Otherwise, i.e. if you believe there are more than one solutions with different values of \(K\) for the given puzzle, choose "Multiple solutions."
Note: Unlike standard Sudoku, KenKen can have cage(s) with repeated digits.
Hint: Observe the structure of this puzzle carefully. What can be said about those tetrominoes and the numbers in each row and column?