C++经典练习例题很多程序的例子很实用

#include <iostream> #include <string> #include <map> using namespace std; //创建map的实例，整数(int)映射字符串(string) typedef map<int, string> INT2STRING; //测试map容器 void main() { //创建map对象theMap INT2STRING theMap; INT2STRING::iterator theIterator,it; //向theMap容器中添入数据，数字和字符串配对 //每个元素是一个映射对 theMap.insert(INT2STRING::value_type(0,"Zero")); theMap.insert(INT2STRING::value_type(2,"Two")); theMap.insert(INT2STRING::value_type(4,"Four")); theMap.insert(INT2STRING::value_type(6,"Six")); theMap.insert(INT2STRING::value_type(8,"Eight")); //显示map容器的所有对象 cout<<"theMap.begin()--theMap.end():"<<endl; for (theIterator=theMap.begin();theIterator!=theMap.end();++theIterator){ cout<<(*theIterator).first; cout<<","<<(*theIterator).second<<" "; } cout<<endl; //测试map容器key的惟一性 theMap.insert(INT2STRING::value_type(0,"Zero")); theMap.insert(INT2STRING::value_type(1,"One")); theMap.insert(INT2STRING::value_type(2,"Two")); theMap.insert(INT2STRING::value_type(3,"Three")); theMap.insert(INT2STRING::value_type(4,"Four")); theMap.insert(INT2STRING::value_type(5,"Five")); theMap.insert(INT2STRING::value_type(6,"Six")); theMap.insert(INT2STRING::value_type(7,"Seven")); theMap.insert(INT2STRING::value_type(8,"Eight")); theMap.insert(INT2STRING::value_type(9,"Nine")); //下列语句将不能插入到map容器中 theMap.insert(INT2STRING::value_type(5,"AAA")); //显示map容器的所有对象 cout<<"theMap.begin()--theMap.end():"<<endl; for (theIterator=theMap.begin();theIterator!=theMap.end();++theIterator){ cout<<(*theIterator).first; cout<<","<<(*theIterator).second<<" "; } cout<<endl; //按键给定的区间显示序列中的元素 cout<<"[theMap.lower_bound(3),theMap.upper_bound(8)] :"<<endl; for (it=theMap.lower_bound(3);it!=theMap.upper_bound(8);it++) { cout<<(*it).first; cout<<","<<(*it).second<<" "; } cout<<endl; //显示theMap的状态信息 cout<<"theMap.size():"<<theMap.size()<<endl; cout<<"theMap.max_size():"<<theMap.max_size()<<endl; cout<<"theMap.count(15):"<<theMap.count(15)<<endl; // 从键盘上输入数字，显示对应的字符串 string theString = ""; int index; for( ; ; ) { cout << "Enter \"q\" to quit, or enter a Number: "; cin >> theString; if(theString == "q") break; for(index = 0; index < theString.length(); index++){ theIterator = theMap.find(theString[index] - '0'); if(theIterator != theMap.end() ) cout << (*theIterator).second << " "; else cout << "[err] "; } cout << endl; } }