Problem F
Sign of a Matrix
Input: Standard Input
Output: Standard Output
You have a n x n
zero matrix. In each operation, you can add one (or minus 1) to every
element of a whole row, or add one (or minus 1) to every element of a whole
column. Given the target signs of every element of the matrix, how many
operations are needed?
Input
There
will be at most 100 test cases. Each test case begins with a line containing a
single integer n (2 ≤ n ≤ 100), followed by n
lines of n characters in each line. Each character is one of +, -
or 0, corresponding to positive, negative and zero, respectively.
Output
For each test case, print the case number and the minimum number of operations
needed. If the target cannot be reached, print -1.
Sample Input Output for Sample Input
|
4 -1 |
Case 1:
3 Case 2: -1 |
Sample elaboration:
For the first sample input, target can be
achieved by 3 moves only. By increasing the second column twice and decreasing
the second row once. Which will convert the initial matrix to
the following-
0 +2 0
0
-1 +1 -1 -1
0 +2
0 0
0 +2
0 0
Which
is the target matrix.
Problemsetter: Rujia Liu
Refurbished by: Sohel Hafiz
Special Thanks: Arifuzzaman Arif