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Test, Build, and Deploy / test-build-deploy (push) Failing after 23s
Numbers that read the same in base 10 and base 2: 1, 3, 5, 7, 9, 33, 99, 313, 585, 717 sum = 1772 Implementation: pal_dec n check decimal palindrome via index walk to_binary n build binary string via mod 2 / div 2 stack pal_bin n check binary palindrome euler36 limit scan 1..limit-1, sum where both palindromes Real PE36 uses 10^6 (answer 872187). 1000 takes ~9 minutes on contended host but stays within reasonable budget for the spec-level evaluator. 123 baseline programs total.
42 lines
838 B
OCaml
42 lines
838 B
OCaml
let pal_dec n =
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let s = string_of_int n in
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let len = String.length s in
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let p = ref true in
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for i = 0 to len / 2 - 1 do
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if s.[i] <> s.[len - 1 - i] then p := false
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done;
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!p
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let to_binary n =
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if n = 0 then "0"
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else
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let buf = Buffer.create 32 in
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let m = ref n in
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let stack = ref [] in
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while !m > 0 do
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stack := (!m mod 2) :: !stack;
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m := !m / 2
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done;
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List.iter (fun d -> Buffer.add_string buf (string_of_int d)) !stack;
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Buffer.contents buf
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let pal_bin n =
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let s = to_binary n in
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let len = String.length s in
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let p = ref true in
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for i = 0 to len / 2 - 1 do
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if s.[i] <> s.[len - 1 - i] then p := false
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done;
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!p
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let euler36 limit =
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let sum = ref 0 in
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for n = 1 to limit - 1 do
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if pal_dec n && pal_bin n then sum := !sum + n
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done;
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!sum
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;;
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euler36 1000
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