#include<stdio.h>
int main()
{
    long int a, ans,n,i,x,y;
    scanf("%ld", &n);
    for (i = 0; i < n; i++)
    {
        scanf("%ld%ld", &x, &y);
        if (x == 1 || y == 1)
        {
            if (x == 1)
                ans = y / 2;
            else if (y == 1)
                ans = x / 2;
        }
        else if (x==2&&y==2)
        {
            ans = 2;
        }
        else 
        {
            ans = x / 2 + y / 2;
        }
        printf("%ld\n", ans);
    }
    return 0;
}