uva solve problem 10812

#include<stdio.h>
int main()
{
    long int n,a,b,result,r,k,i;
    while(scanf("%ld",&n)!=EOF)
    {
        for(i=0;i<n;i++)
        {
            scanf("%ld%ld",&a,&b);
            if((a<b)||((a%2==1)&&(b%2==0))||((b%2==1)&&(a%2==0)))
            printf("impossible\n");
            else
            {
            k=(a-b)/2;
            result=b+k;
            printf("%ld %ld\n",result,k);
            }
        }
    }
    return 0;
}