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(* Title: HOL/SPARK/Manual/Simple_Greatest_Common_Divisor.thy
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45044
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Author: Stefan Berghofer
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Copyright: secunet Security Networks AG
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*)
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theory Simple_Greatest_Common_Divisor
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imports SPARK GCD
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begin
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spark_proof_functions
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gcd = "gcd :: int \<Rightarrow> int \<Rightarrow> int"
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spark_open "simple_greatest_common_divisor/g_c_d.siv"
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spark_vc procedure_g_c_d_4
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using `0 < d` `gcd c d = gcd m n`
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by (simp add: gcd_non_0_int)
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spark_vc procedure_g_c_d_9
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using `0 \<le> c` `gcd c 0 = gcd m n`
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by simp
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spark_end
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end
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