zoj 2388 Beat the Spread!

#include <stdio.h>#include <string.h>#include <map>#include <vector>#include <algorithm>using namespace std;int a[1000];int main(){ int i,j,n,T,s,x,y,z,ans; scanf("%d",&T); while(T--) { scanf("%d%d",&x,&y); if (x<y || (x+y)%2!=0) { printf("impossiblen"); } else { printf("%d %dn",(x+y)/2,(x-y)/2); } } return 0;}