57 lines
2.4 KiB
C
57 lines
2.4 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
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│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
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╞══════════════════════════════════════════════════════════════════════════════╡
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│ Copyright 2020 Justine Alexandra Roberts Tunney │
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│ │
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│ This program is free software; you can redistribute it and/or modify │
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│ it under the terms of the GNU General Public License as published by │
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│ the Free Software Foundation; version 2 of the License. │
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│ │
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│ This program is distributed in the hope that it will be useful, but │
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│ WITHOUT ANY WARRANTY; without even the implied warranty of │
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│ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU │
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│ General Public License for more details. │
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│ │
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│ You should have received a copy of the GNU General Public License │
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│ along with this program; if not, write to the Free Software │
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│ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA │
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│ 02110-1301 USA │
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╚─────────────────────────────────────────────────────────────────────────────*/
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#include "libc/math.h"
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#if 1
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#define FLOAT long double
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#define SQRT sqrtl
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#else
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#define FLOAT float
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#define SQRT sqrt
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#endif
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/**
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* Computes π w/ François Viète method.
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*
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* make -j8 MODE=tiny
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* o/tiny/tool/build/emulator.com.dbg -t o/tiny/tool/build/pi.bin
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*
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*/
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FLOAT Main(void) {
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long i, n;
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FLOAT pi, q, t;
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n = VEIL("r", 10);
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q = 0;
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t = 1;
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for (i = 0; i < n; ++i) {
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q += 2;
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q = SQRT(q);
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t *= q / 2;
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}
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return 2 / t;
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}
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volatile FLOAT st0;
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int main(int argc, char *argv[]) {
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st0 = Main();
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return 0;
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}
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