Yes, all six can cross the river safely, even with the rowing restriction and the fear of missionaries being outnumbered.

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Let’s label the missionaries as M, m, m and the cannibals as K, k, k, where M (missionary) and K (cannibal) are the only ones who can row the boat.

1. K (the rowing cannibal) takes k across the river.
2. K returns alone.
   (Now: K, M, m, m on the original side; k, k on the far side)
3. M and m cross together.
4. M and k return.
   (Now: K, K, M, m on far side; M, k, m on original side)
5. The other M and m cross again.
6. K returns alone.
   (Now: K, k, k on original side; M, m, m on far side)
7. Finally, K takes k across, returns, and then ferries the last k across.

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