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//===-- llvm/ADT/SetOperations.h - Generic Set Operations -------*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file defines generic set operations that may be used on set's of
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// different types, and different element types.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_ADT_SETOPERATIONS_H
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#define LLVM_ADT_SETOPERATIONS_H
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/// set_union(A, B) - Compute A := A u B, return whether A changed.
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template <class S1Ty, class S2Ty>
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bool set_union(S1Ty &S1, const S2Ty &S2) {
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for (typename S2Ty::const_iterator SI = S2.begin(), SE = S2.end();
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if (S1.insert(*SI).second)
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/// set_intersect(A, B) - Compute A := A ^ B
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/// Identical to set_intersection, except that it works on set<>'s and
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/// is nicer to use. Functionally, this iterates through S1, removing
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/// elements that are not contained in S2.
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template <class S1Ty, class S2Ty>
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void set_intersect(S1Ty &S1, const S2Ty &S2) {
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for (typename S1Ty::iterator I = S1.begin(); I != S1.end();) {
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const typename S1Ty::key_type &E = *I;
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if (!S2.count(E)) S1.erase(E); // Erase element if not in S2
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/// set_difference(A, B) - Return A - B
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template <class S1Ty, class S2Ty>
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S1Ty set_difference(const S1Ty &S1, const S2Ty &S2) {
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for (typename S1Ty::const_iterator SI = S1.begin(), SE = S1.end();
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if (!S2.count(*SI)) // if the element is not in set2
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/// set_subtract(A, B) - Compute A := A - B
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template <class S1Ty, class S2Ty>
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void set_subtract(S1Ty &S1, const S2Ty &S2) {
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for (typename S2Ty::const_iterator SI = S2.begin(), SE = S2.end();
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} // End llvm namespace