26 lines
493 B
C
26 lines
493 B
C
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/*
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Copyright (c) 2013 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Author: Leonardo de Moura
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*/
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namespace lean {
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/**
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\brief Template for computing <tt>a^k</tt>.
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*/
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template<typename T>
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T power(T const & a, unsigned k) {
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unsigned mask = 1;
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T power = a;
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T b = 1;
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while (mask <= k) {
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if (mask & k)
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b *= power;
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power *= power;
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mask = mask << 1;
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}
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return b;
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}
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}
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