ll@t; rep(t){ ll@n; ll a=0; ll b=3d5; rep(n){ string@x,@y; if(x=="a"){ a>?=y.size(); if(find(y.begin(),y.end(),'a')!=y.end()){ b=0; } } if(find(x.begin(),x.end(),'a')==x.end()){ b=b?"Yes":"No"); }