#include <cstdio>#include <cstdlib>#include <cmath>using namespace std;int cmp(const void* a,const void* b){ int* c=(int*)a; int* d=(int*)b; return *c-*d>=0;}int main(){ int n,m,n1[110],n2[110],i,total1,total2,dif,j,f; while(1) { scanf("%d %d",&n,&m); if(0==n&&0==m) break; total1=0,total2=0; for(i=0;i<n;i++) { scanf("%d",&n1[i]); total1+=n1[i]; } for(i=0;i<m;i++) { scanf("%d",&n2[i]); total2+=n2[i]; } dif=(int)abs(double(total2-total1)); if(dif%2==1) { printf("-1n");continue; } qsort(n1,n,sizeof(int),cmp); qsort(n2,m,sizeof(int),cmp); if(total2>total1) { f=0; for(i=0;i<n&&0==f;i++) { for(j=0;j<m;j++) { if((n2[j]-n1[i])*2==dif) { printf("%d %dn",n1[i],n2[j]); f=1;break; } else if((n2[j]-n1[i])*2>dif) break; } } if(0==f) printf("-1n"); } else if(total2==total1) { f=0; for(i=0;i<n&&0==f;i++) { for(j=0;j<m;j++) { if(n1[i]==n2[j]) { printf("%d %dn",n1[i],n2[j]); f=1;break; } else if(n2[j]>n1[i]) break; } } if(0==f) printf("-1n"); } else if(total2<total1) { f=0; for(i=0;i<n&&0==f;i++) { for(j=0;j<m;j++) { if((n1[i]-n2[j])*2==dif) { printf("%d %dn",n1[i],n2[j]); f=1;break; } else if((n1[i]-n2[j])*2<dif) break; } } if(0==f) printf("-1n"); } } return 0;}
