Chess - Programming - FEN (Forsyth-Edwards Notation) - Test Pawn Shield

In all these positions, white has a pawn shield at least as good as black.

6k1/5p1p/8/8/8/8/5PPP/6K1 w - - 0 1
6k1/5p1p/6p1/8/8/8/5PPP/6K1 w - - 0 1
6k1/7p/5pp1/8/8/6P1/5P1P/6K1 w - - 0 1
6k1/7p/5pp1/8/8/8/5PPP/6K1 w - - 0 1
6k1/6pp/5p2/8/8/8/5PPP/6K1 w - - 0 1
6k1/8/5ppp/8/8/6PP/5P2/6K1 w - - 0 1
6k1/8/5ppp/8/8/5P1P/6P1/6K1 w - - 0 1
6k1/5p2/6pp/8/8/6P1/5P1P/6K1 w - - 0 1
6k1/5p2/6pp/8/8/7P/5PP1/6K1 w - - 0 1
8/5pkp/6p1/8/8/6P1/5P1P/6K1 w - - 0 1
1k6/p1p5/1p6/1P4p1/8/6P1/5P1P/6K1 w - - 0 1