= Incomplete positively curved strip with infinite diameter
{title2=$g=du^2+\cos^2u\,dv^2,\quad|u|<\pi/4,\quad v\in\mathbb R$}
This metric pulls back the round spherical metric by $(u,v)\mapsto(\cos u\cos v,\cos u\sin v,\sin u)$. It has unit <Gaussian curvature> and <Ricci curvature> equal to its metric, yet the meridian reaches a missing boundary in finite time. Every curve between $(0,0)$ and $(0,L)$ has length at least $|L|/\sqrt2$, so its diameter is infinite. It shows that the positive Ricci bound alone does not replace <geodesic completeness> in the <Bonnet-Myers theorem>.
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