Solutions to Cannibals and Marvels

Here are the Casual-Observer's solutions to last week's puzzles. It's very likely that there are other, equally good solutions. If you find a more efficient one, let us know!

Puzzle 1: Cannibals and Missionaries
To keep the missionaries from proselytizing, as they will do if they outnumber the cannibals, do as follows:

1 missionary and 1 cannibal there, cannibal back. 2 missionaries there, 1 missionary back. 2 cannibals there, 1 cannibal and 1 missionary back. 2 cannibals there, 1 missionary back. 2 missionaries there, 1 missionary back. 2 missionaries there.

Puzzle 2: Stranded in Valhalla
Our solution takes 17 one-way crossings. We do it thusly:

1. Ryan Reynolds and Chris Pratt there
2. Ryan Reynolds back
3. Ryan Reynolds and Chris Hemsworth there
4. Ryan Reynolds and Chris Pratt back
5. Rocco and Liam Hemsworth there
6. Rocco back
7. Rocco and Taika Waititi there
8. Taika Waititi back
9. Ryan Reynolds and Chris Pratt there
10. Rocco back
11. Taika Waititi and Rocco there
12. Taika Waititi back
13. Taika Waititi and Iman Vellani there
14. Ryan Reynolds and Chris Pratt back
15. Ryan Reynolds and Brie Larson there
16. Ryan Reynolds back
17. Ryan Reynolds and Chris Pratt there