泛型算法（九）之替换算法

1、replace(ForwardIterator first, ForwardIterator last, const T& old_value, const T& new_value)：把序列中为给定值的元素替换为新值

    std::vector<int> c;
    c.reserve(10);
    //向c中添加元素
    for (int i = 0; i < 10; i++)
    {
        c.push_back(i);
    }
    //把序列c中值等于5的元素替换成100
    std::replace(c.begin(), c.end(), 5, 100);
    //输出c
    for (auto var : c)
    {
        std::cout << var << ",";
    }
    //打印结果：0,1,2,3,4,100,6,7,8,9,

2、replace_if(ForwardIterator first, ForwardIterator last, UnaryPredicate pred, const T& new_value)：把序列中满足给定谓词pred的元素替换为新值

    std::vector<int> c;
    c.reserve(10);
    //向c中添加元素
    for (int i = 0; i < 10; i++)
    {
        c.push_back(i);
    }
    //把序列c中值大于5的元素替换成100
    std::replace_if(c.begin(), c.end(), [](int element){
        return element > 5;
    }, 100);
    //输出c
    for (auto var : c)
    {
        std::cout << var << ",";
    }
    //打印结果：0,1,2,3,4,5,100,100,100,100,

3、replace_copy(InputIterator first, InputIterator last, OutputIterator result, const T& old_value, const T& new_value)复制序列，对于等于老值的元素复制时使用新值

    std::vector<int> c;
    std::vector<int> result;
    c.reserve(10);
    result.resize(10);
    //向c中添加元素
    for (int i = 0; i < 10; i++)
    {
        c.push_back(i);
    }
    //复制c到result中，对于c中等于5的元素在复制时用100代替
    std::replace_copy(c.begin(), c.end(), result.begin(), 5, 100);
    //输出result
    for (auto var : result)
    {
        std::cout << var << ",";
    }
    //打印结果：0,1,2,3,4,100,6,7,8,9,

4、replace_copy_if(InputIterator first, InputIterator last, OutputIterator result, UnaryPredicate pred, const T& new_value)：复制序列，对于满足给定谓词pred的元素复制新值

    std::vector<int> c;
    std::vector<int> result;
    c.reserve(10);
    result.resize(10);
    //向c中添加元素
    for (int i = 0; i < 10; i++)
    {
        c.push_back(i);
    }
    //复制c到result中，对于c中大于5的元素在复制时用100代替
    std::replace_copy_if(c.begin(), c.end(), result.begin(), [](int element){
        return element > 5;
    }, 100);
    //输出result
    for (auto var : result)
    {
        std::cout << var << ",";
    }
    //打印结果：0,1,2,3,4,5,100,100,100,100,