ALL: Add flint

external/flint-2.4.3/examples/multi_crt.cpp

@@ -0,0 +1,73 @@
+/*=============================================================================
+
+    This file is part of FLINT.
+
+    FLINT is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    FLINT is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with FLINT; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
+
+=============================================================================*/
+/******************************************************************************
+
+    Copyright (C) 2011 Fredrik Johansson
+    Copyright (C) 2013 Tom Bachmann (C++ adaptation)
+
+******************************************************************************/
+
+/*
+    Demo FLINT program for balanced multimodular reduction and
+    reconstruction using the Chinese Remainder Theorem.
+*/
+
+#include <iostream>
+#include <vector>
+#include "fmpzxx.h"
+#include "ulong_extras.h"
+
+using namespace flint;
+
+int main(int argc, char* argv[])
+{
+    if (argc != 3)
+    {
+        std::cerr << "Syntax: crt <integer> <num_primes>\n";
+        return 1;
+    }
+
+    slong num_primes = atoi(argv[2]);
+
+    if (num_primes < 1)
+    {
+        std::cerr << "Requires num_primes >= 1\n";
+        return 2;
+    }
+
+    fmpzxx x(argv[1]);
+
+    std::vector<mp_limb_t> primes(num_primes), residues(num_primes);
+    primes[0] = 2;
+    for (unsigned i = 1; i < num_primes; i++)
+        primes[i] = n_nextprime(primes[i-1], 0);
+
+    fmpz_combxx comb(primes);
+    multi_mod(residues, x, comb);
+
+    for (unsigned i = 0; i < num_primes; i++)
+        std::cout << "residue mod " << primes[i]
+                  << " = " << residues[i] << '\n';
+
+    std::cout << "reconstruction = " << multi_CRT(residues, comb, true)
+              << '\n';
+
+    return 0;
+}