ll f(Matrixa){ ll y=0,x=0; while(ya(l,m),b(m,n),c; rd(a(l,m),b(m,n)); c=a*b; rep(i,l)rep(j,n)if(c[i][j]){ wt("No"); exit(0); } if(f(a)+f(b)!=l){ wt("No"); exit(0); } wt("Yes"); }