#include int ask(int x,int y){ printf("%d %d\n",x,y); fflush(stdout); int d; scanf("%d",&d); return d; } void run(void){ int d=ask(0,0); if(d==0) return; int e=ask(0,d); if(e==0) return; int a=d-e/2; int b=e/2; ask(a,b); return; } int main(void){ run(); return 0; }