char s[3d5]; ll n,t[2d5],u[2d5],v[2d5],h[128]; ll nib(ll a,ll b){ ll c=min(a,n-1-b)+1; ll d=0; while(d0) r>?=b+1-a+(d+nib(a-d-1,b+d))*2; if(b+d?=b+1-a+(d+nib(a-d,b+d+1))*2; } wt(r); } }