src/HOL/Extraction/Pigeonhole.thy
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parent 23810 f5e6932d0500
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     4 *)
     4 *)
     5 
     5 
     6 header {* The pigeonhole principle *}
     6 header {* The pigeonhole principle *}
     7 
     7 
     8 theory Pigeonhole
     8 theory Pigeonhole
     9 imports EfficientNat
     9 imports Efficient_Nat
    10 begin
    10 begin
    11 
    11 
    12 text {*
    12 text {*
    13 We formalize two proofs of the pigeonhole principle, which lead
    13 We formalize two proofs of the pigeonhole principle, which lead
    14 to extracted programs of quite different complexity. The original
    14 to extracted programs of quite different complexity. The original