Rikka with Chess

Yuta gives Rikka a chess board of size n×m . As we all know, on a chess board, every cell is either black or white and every two cells that share a side have different colors. Rikka can choose any rectangle formed by board squares and perform an inversion, every white cell becomes black, and vice versa. Rikka wants to turn all cells into the same color, please tell Rikka the minimal number of inversions she need to achieve her goal.

The first line contains a number T(T≤10) ——The number of the testcases. Each testcase contains two numbers n,m(n≤109,m≤109) .

For each testcase, print a single number which represents the answer.

31 22 23 3

122

/*思路：刚看到题目被吓到，然后画图猜，发现这个规律，所以不要被题目吓到.. */#include
    
     using namespace std;int main(){      int n,m,t;    cin>>t;    while(t--){    	cin>>n>>m;    	cout<