[C++ code]
[cpp]
/*
*@author:郑海波 http://blog.csdn.net/NUPTboyZHB
*参考:实验室小熊
*注:有删改
*/
#pragma warning(disable:4786)
#include
#include
#include
#include
#include
#include
#include
using namespace std;
void topK(const int &K)
{
double t=clock();
ifstream infile("test.txt");
if (!infile)
cout<<"can not open file"<
string s="";
mapwordcount;
unsigned char temp[2];
while(true)//国标2312
{
infile>>temp[0];
if(infile.eof()) break;
if (temp[0]>=0xB0)//GB2312下的汉字,最小是0XB0
{
s+=temp[0];
infile>>temp[1];
s+=temp[1];
}
else//非汉字字符不统计
{
s="";
continue;
}
wordcount[s]++;
s="";
}
cout<<"单词种类:"<
//优先队列使用小顶堆,排在前面的数量少,使用">";
priority_queue< pair< int,string >,vector< pair< int,string > >,greater< pair< int,string> > > queueK;
for (map::iterator iter=wordcount.begin(); iter!=wordcount.end(); iter++)
{
queueK.push(make_pair(iter->second,iter->first));
if(queueK.size()>K)
queueK.pop();
}
pairtmp;
//将排在后面的数量少,排在前面的数量多
priority_queue< pair< int,string >,vector< pair< int,string > >,less< pair< int,string> > > queueKless;
while (!queueK.empty())
{
tmp=queueK.top();
queueK.pop();
queueKless.push(tmp);
}
while(!queueKless.empty())
{
tmp=queueKless.top();
queueKless.pop();
cout<
}
cout<<"< Elapsed Time: "<<(clock()-t)/CLOCKS_PER_SEC<<" s>"<
cin>>k;
}
int main()
{
int k=0;
cout<<"http://blog.csdn.net/NUPTboyZHB\n";
while (true)
{
cout<<"查看前K个频率最高的汉字,K=";
if(k<=0)break;
topK(k);
}
return 0;
}
[图1]
2.统计英文单词的出现频率。这比统计汉字更加的容易,因为单词和单词之间是用空格分开的,所以,直接将单词保存到string中即可。
[c++ code]
[cpp]
/*
*@author:郑海波 http://blog.csdn.net/NUPTboyZHB
*参考:实验室小熊
*注:有删改
*/
#pragma warning(disable:4786)
#include
#include
#include
#include
#include
#include
#include
using namespace std;
void topK(const int &K)
{
double t=clock();
ifstream infile;
infile.open("test.txt");
if (!infile)
cout<<"can not open file"<
string s;
mapwordcount;
while(true)
{
infile>>s;
if(infile.eof()) break;
wordcount[s]++;
}
cout<<"单词种类:"<
//优先队列使用小顶堆,排在前面的数量少,使用">";
priority_queue< pair< int,string >,vector< pair< int,string > >,greater< pair< int,string> > > queueK;
for (map::iterator iter=wordcount.begin(); iter!=wordcount.end(); iter++)
{
queueK.push(make_pair(iter->second,iter->first));
if(queueK.size()>K)
queueK.pop();
}
pairtmp;
priority_queue< pair< int,string >,vector< pair< int,string > >,less< pair< int,string> > > queueKless;
while (!queueK.empty())
{
tmp=queueK.top();
queueK.pop();
queueKless.push(tmp);
}
while(!queueKless.empty())
{
tmp=queueKless.top();
queueKless.pop();
cout<
}
cout<<"< Elapsed Time: "<<(clock()-t)/CLOCKS_PER_SEC<<" >"<
}
int main()
{
int k=0;
cout<<"http://blog.csdn.net/NUPTboyZHB\n";
while (true)
{
cout<<"PUT IN K: ";
cin>>k;
if(k<=0)break;
topK(k);
}
return 0;
}
[图2]