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STL之map::find方法的使用小例子

函式原型

iterator find (const key_type& k);
const_iterator find (const key_type& k) const;

返回值

An iterator to the element, if an element with specified key is found, or map::end otherwise.

If the map object is const-qualified, the function returns a const_iterator. Otherwise, it returns an
iterator.
Member types iterator and const_iterator are bidirectional iterator types pointing to elements (of type value_type). Notice that value_type in map containers is an alias of pair<const key_type, mapped_type>.

例子

//map::find
#include <iostream>
#include <map>

int main ()
{
    std
::map<char,int> mymap; std::map<char,int>::iterator it; mymap['a']=50; mymap['b']=100; mymap['c']=150; mymap['d']=200; it = mymap.find('b'); if (it != mymap.end()) mymap.erase (it); // print content: std::cout << "elements in mymap:" << '\n'
; std::cout << "a => " << mymap.find('a')->second << '\n'; std::cout << "c => " << mymap.find('c')->second << '\n'; std::cout << "d => " << mymap.find('d')->second << '\n'; std::cout << "b => " << mymap.find('b')->second << '\n'; std::cout << "e => " << mymap.find('e')->second << '\n'; return 0; }

執行結果

Output:

elements in mymap:
a => 50
c => 150
d => 200
b => 0
e => 0