第十五周项目：范型程序

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/* *Copyright(c)2016.烟台大学计算机学院 *All right reserved. *文件名称：test.cpp *作者：黄金婵 *完成日期：2016年6月24日 *版本号：v1.0 * *问题描述： *程序输入： *程序输出： */#include <map>#include <iostream>using namespace std;int main( ){    map <int, int> m1, m2, m3;    map <int, int>::iterator m1_Iter;    m1.insert ( pair <int, int>  ( 1, 10 ) );    m1.insert ( pair <int, int>  ( 2, 20 ) );    m1.insert ( pair <int, int>  ( 3, 30 ) );    m2.insert ( pair <int, int>  ( 10, 100 ) );    m2.insert ( pair <int, int>  ( 20, 200 ) );    m3.insert ( pair <int, int>  ( 30, 300 ) );    cout << "The original map m1 is:";    for ( m1_Iter = m1.begin( ); m1_Iter != m1.end( ); m1_Iter++ )        cout << " " << m1_Iter->second;    cout   << "." << endl;    // This is the member function version of swap    //m2 is said to be the argument map; m1 the target map    m1.swap( m2 );    cout << "After swapping with m2, map m1 is:";    for ( m1_Iter = m1.begin( ); m1_Iter != m1.end( ); m1_Iter++ )        cout << " " << m1_Iter -> second;    cout  << "." << endl;    cout << "After swapping with m2, map m2 is:";    for ( m1_Iter = m2.begin( ); m1_Iter != m2.end( ); m1_Iter++ )        cout << " " << m1_Iter -> second;    cout  << "." << endl;    // This is the specialized template version of swap    swap( m1, m3 );    cout << "After swapping with m3, map m1 is:";    for ( m1_Iter = m1.begin( ); m1_Iter != m1.end( ); m1_Iter++ )        cout << " " << m1_Iter -> second;    cout   << "." << endl;    return 0;}

知识点总结：

在构造map容器后，我们就往里面插入数据。用insert函数插入pair数据，用insert函数插入数据，在数据的插入上涉及到集合的唯一性这个概念，即当map中有这个关键字时，insert操作是插入数据不了的，但是用数组方式就不同了，它可以覆盖以前该关键字对应的值，用程序说明

 m1.insert ( pair <int, int>  ( 1, 10 ) );

 m1.insert ( pair <int, int>  ( 2, 20 ) ); m1.insert ( pair <int, int>  ( 3, 30 ) ); m2.insert ( pair <int, int>  ( 10, 100 ) ); m2.insert ( pair <int, int>  ( 20, 200 ) ); m3.insert ( pair <int, int>  ( 30, 300 ) );

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