统计计数

#include<iostream>
#include<stdlib.h>
#include<set>
using namespace std;

//multiset
int main()
{
    srand(time(0));
    multiset<int> ms;//允许每次插入每个值的多个对象
    for(int i=0;i<20;i++)
        ms.insert(rand()%10);
    typedef multiset<int>::iterator miter;
    miter iter = ms.begin();
    while(iter!=ms.end()){
        pair<miter,miter> p = ms.equal_range(*iter);//产生当前选中的韵语的起始和终止迭代器
        int count = distance(p.first,p.second);//对在iterator中定义的范围内的元素进行计数
        cout << *iter << ": " << count << endl;
        iter = p.second;
    }
}

//map
int main()
{
    ifstream in("/home/xiangjie/code/thinking/T207/a.txt");
    string word;
    map<string,int> wc;
    while(in>>word){
        wc[word]++;
    }
    for(map<string,int>::iterator iter=wc.begin();
                                  iter!=wc.end();
                                  ++iter)
    {
        cout << iter->first << ":" << iter->second << endl;
    }
}