Problem Statement | |||||||||||||
A two-dimensional array of integers is positive if the sum of all elements in each row and each column is strictly greater than zero. For example, the following array is positive: 2 1 -1 -1 2 2 , while the next one is not: 1 1 -1 -1 2 2 (the sum of the elements in the first column is 0). You will be given a String[] data, representing a 2-d array. The j-th character of the i-th element of data represents the j-th number in the i-th row of the array. Digits ('0'-'9') denote numbers between 0 and 9, lowercase letters ('a'-'z') denote numbers between 10 and 35, respectively, and uppercase letters ('A'-'Z') denote negative numbers between -1 and -26, respectively. For example, 'a' represents 10, 'c' represents 12, 'A' represents -1 and 'Z' represents -26. In one move you are allowed to change the signs of all numbers in some row or column (i.e., multiply all numbers in a row or in a column by -1). Return the minimal number of moves you'll need to get a positive array, or -1 if this is impossible. | |||||||||||||
Definition | |||||||||||||
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Constraints | |||||||||||||
| - | data will contain between 1 and 18 elements, inclusive. | ||||||||||||
| - | Each element of data will contain between 1 and 18 characters, inclusive. | ||||||||||||
| - | Each element of data will contain only digits ('0'-'9') or letters ('a'-'z', 'A'-'Z'). | ||||||||||||
| - | All elements of data will have the same length. | ||||||||||||
Examples | |||||||||||||
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