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/* ************************************************************** * C++ Mathematical Expression Toolkit Library * * * * ExprTk Ten Thousand Digits Of E via Spigot Algorithm * * Author: Arash Partow (1999-2024) * * URL: https://www.partow.net/programming/exprtk/index.html * * * * Copyright notice: * * Free use of the Mathematical Expression Toolkit Library is * * permitted under the guidelines and in accordance with the * * most current version of the MIT License. * * https://www.opensource.org/licenses/MIT * * SPDX-License-Identifier: MIT * * * ************************************************************** */ #include #include #include "exprtk.hpp" template void e_10k_digits() { typedef exprtk::symbol_table symbol_table_t; typedef exprtk::expression expression_t; typedef exprtk::parser parser_t; symbol_table_t symbol_table; symbol_table.add_function("print", [](T t) -> T { printf("%1d",static_cast(t)); return T(1); }); const std::string e_10k_digits_spigot = " const var num_digits := 10000; " " var a[num_digits] := [2:1]; " " var b[num_digits] := [1]; " " " " print(2); " " " " for (var digit := 0; digit < num_digits; digit += 1) " " { " " b *= 10; " " " " for (var i := (b[] - 1); i > 0; i -= 1) " " { " " var q := floor(b[i] / a[i]); " " var r := floor(b[i] % a[i]); " " b[i - 1] := b[i - 1] + q; " " b[i] := r; " " }; " " " " print(floor(b[0] / a[0])); " " " " b[0] %= a[0]; " " } "; expression_t expression; expression.register_symbol_table(symbol_table); parser_t parser; parser.compile(e_10k_digits_spigot,expression); expression.value(); } int main() { e_10k_digits(); return 0; }