Time Limit: 1.5 sec
After a test of a code, Mina detect X errors and Rina discovered Y errors in the same code. There are Z errors in common.
If the total error are A, estimate the number of errors that are still undetected.
The first line contains a positive integer T ( 1<=T<=100000), denoting the number of test cases. The next T lines will contain 4 integers X, Y, Z, and A.
For each test case, output one line in the format "Case m: n" (quotes for clarity), where m is the case number and n is the number of errors that are still undetected by Mina and Rina.
2 3 1 6
5 3 2 10
Case 1: 2
Case 2: 4
Online Practice Contest 2 [School & College Level]
Problem Setter: Shahin ShamS