funadap.cpp

一本很好的C++学习的丛书！初学者必看的

// funadap.cpp -- using function adapters
#include <iostream>
#include <vector>
#include <iterator>
#include <algorithm>
#include <functional>

void Show(double);
const int LIM = 5;
int main()
{
    using namespace std;
    double arr1[LIM] = {36, 39, 42, 45, 48};
    double arr2[LIM] = {25, 27, 29, 31, 33};
    vector<double> gr8(arr1, arr1 + LIM);
    vector<double> m8(arr2, arr2 + LIM);
    cout.setf(ios_base::fixed);
    cout.precision(1);
    cout << "gr8:\t";
    for_each(gr8.begin(), gr8.end(), Show);
    cout << endl;
    cout << "m8: \t";
    for_each(m8.begin(), m8.end(), Show);
    cout << endl;

    vector<double> sum(LIM);
    transform(gr8.begin(), gr8.end(), m8.begin(), sum.begin(),
              plus<double>());
    cout << "sum:\t";
    for_each(sum.begin(), sum.end(), Show);
    cout << endl;

    vector<double> prod(LIM);
    transform(gr8.begin(), gr8.end(), prod.begin(),
              bind1st(multiplies<double>(), 2.5));
    cout << "prod:\t";
    for_each(prod.begin(), prod.end(), Show);
    cout << endl;

    return 0; 
}

void Show(double v)
{
    std::cout.width(6);
    std::cout << v << ' '; 
}