casbin/util/array_remove_duplicates.cpp

/*
 * Copyright 2020 The casbin Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "casbin/pch.h"

#ifndef ARRAY_REMOVE_DUPLICATES_CPP
#define ARRAY_REMOVE_DUPLICATES_CPP

#include <unordered_map>

#include "casbin/util/util.h"

namespace casbin {

// ArrayRemoveDuplicates removes any duplicated elements in a std::string array.
void ArrayRemoveDuplicates(std::vector<std::string>& s) {
    std::unordered_map<std::string, bool> found;
    found.reserve(s.size());
    int j = 0;
    for (const std::string& it : s) {
        if (!found[it]) {
            found[it] = true;
            s[j++] = it;
        }
    }
    s.erase(s.begin() + j, s.end());
}

} // namespace casbin

#endif // ARRAY_REMOVE_DUPLICATES_CPP