1358A.ParkLightining.cpp

#include<bits/stdc++.h>
#define ll long long int
using namespace std;
int main(){
	#ifndef ONLINE_JUDGE
       freopen("input.txt","r",stdin);
       freopen("Output.txt","w",stdout);
    #endif
	int  t;
	cin>>t;
	while(t--){
		int  n,m;
		cin>>n>>m;
		//ll blocks = n*m;
		int ans = ((n*m)+1)/2;
		cout<<ans<<"\n"; 
	}
	return 0;
}