#include<stdio.h>
int main()
{
int n,s,d,lar,sma;
scanf("%d",&n);
while(n--)
{
scanf("%d%d",&s,&d);
if(s>=d&&(s+d)%2==0)
{
lar=(s+d)/2;
sma=(s-d)/2;
printf("%d %d\n",lar,sma);
}
else printf("impossible\n");
}
return 0;
}
int main()
{
int n,s,d,lar,sma;
scanf("%d",&n);
while(n--)
{
scanf("%d%d",&s,&d);
if(s>=d&&(s+d)%2==0)
{
lar=(s+d)/2;
sma=(s-d)/2;
printf("%d %d\n",lar,sma);
}
else printf("impossible\n");
}
return 0;
}