1 / transform algorithm example
2 #include <iostream> // std::cout
3 #include <algorithm> // std::transform
4 #include <vector> // std::vector
5 #include <functional> // std::plus
6
7 int op_increase (int i) { return ++i; }
8
9 int main () {
10 std::vector<int> foo;
11 std::vector<int> bar;
12
13 // set some values:
14 for (int i=1; i<6; i++)
15 foo.push_back (i*10); // foo: 10 20 30 40 50
16
17 bar.resize(foo.size()); // allocate space
18
//将foo中的每个元素执行op_increase操作，然后将值写入bar
19 std::transform (foo.begin(), foo.end(), bar.begin(), op_increase);
20 // bar: 11 21 31 41 51
21
//将foo和bar中的每个元素执行plus操作，然后写入第一个元素
22 // std::plus adds together its two arguments:
23 std::transform (foo.begin(), foo.end(), bar.begin(), foo.begin(), std::plus<int>());
24 // foo: 21 41 61 81 101
25
26 std::cout << "foo contains:";
27 for (std::vector<int>::iterator it=foo.begin(); it!=foo.end(); ++it)
28 std::cout << ' ' << *it;
29 std::cout << '\n';
30
31 return 0;
32 }
