UVa 10812

#include<stdio.h>
int main()
{
    unsigned int n,i,x,y,s;
    scanf("%u",&n);
    for(i=1;i<=n;i++){
        scanf("%u %u",&x,&y);
        s=x+y;
        if(x<y || s%2!=0)
            printf("impossible\n");
        else{
            x=s/2;
            y=x-y;
            printf("%d %d\n",x,y);

        }
    }
    return 0;
}