C + + STL Algorithm:std::find, std::find_if

Td::find:

Find container elements, find can only look for container elements for < basic data type >

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2. #include <iostream>
4. #include <vector>
6. #include <algorithm>
8. int main ()
10. {
12. Std::vector<int> v;
14. for (int i = 0; i <; ++i)
16. V.push_back (i);
18. Std::vector<int>::iterator iter = Std::find (V.begin (), V.end (), 3);
20. if (iter = = V.end ())
22. Std::cout << "Can not find value 3 in V" << Std::endl;
24. Else
26. Std::cout << "The index of Value" << (*iter) << "is" << std::d istance (V.begin (), ITER) << Std::endl;
28. return 0;
30. }

Std::find_if

Find a container element conditionally, the container type is < class >, you cannot find it using Find, so use find_if to find

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2. #include <iostream>
4. #include <vector>
6. #include <algorithm>
8. #include <functional>
10. struct POINT
12. {
14. int x;
16. int y;
18. };
20. struct Pointfindbycoord:public std::binary_function<point, point, bool>
22. {
24. BOOL Operator () (const point &OBJ1, const-point &obj2) const
26. {
28. return obj1.x = = obj2.x && Obj1.y = = obj2.y;
30. }
32. };
34. int main ()
36. {
38. Std::vector<point> v;
40. for (int i = 0; i < 5; ++i)
42. {
44. for (int j = 0; j < 5; ++j)
46. {
48. Point pt;
50. Pt.x = i;
52. Pt.y = j;
54. V.push_back (PT);
56. }
58. }
60. Point Needfind;
62. Needfind.x = 4;
64. NEEDFIND.Y = 3;
66. Std::vector<point>::iterator iter = std::find_if (V.begin (), V.end (), std::bind2nd (Pointfindbycoord (), NeedFind ));
68. if (iter = = V.end ())
70. {
72. Not found
74. }
76. Else
78. Std::cout << "The index of Value point (" << (*iter). x << "," << (*iter). Y
80. << "is" << std::d istance (V.begin (), ITER) << Std::endl;
84. return 0;
86. }

C + + STL Algorithm:std::find, std::find_if