区间选点有关问题，求源代码

区间选点问题，求源代码。
区间选点问题

　　【例2】数轴上有n个闭区间[ai,bi]。取尽量少的点，使得每个区间内都至少有一个点（不同区间内含的点可以是同一个）。



[解决办法]
lz画个图就可以了

C/C++ code

#include <iostream>using namespace std;struct  Period {    float begin;    float end;};void Swap(Period &per1,Period &per2){    Period temp;    temp=per1;    per1=per2;    per2=temp;}void Sort(Period *peiodGroup,int len)//pop sort by peiodGroup[i].begin{    int i,j;    for (j=len-1;j>0;j--)    {        for (i=0;i<j;i++)        {            if (peiodGroup[i].begin>peiodGroup[i+1].begin)            {                Swap(peiodGroup[i],peiodGroup[i+1]);            }        }    }}int  Count(Period *peiodGroup,int len)//notice:the peiodGroup has been sorted{    int dotCount=1;    int i;    float curEnd=peiodGroup[0].end;    for (i=1;i<len;i++)    {        if (peiodGroup[i].begin<=curEnd)        {            ;        }        else        {            dotCount++;            curEnd=peiodGroup[i].end;        }    }    return dotCount;}int main(){    int len;    cin>>len;//区间 个数    Period *peiodGroup=new Period[len];    //input    int i;    for (i=0;i<len;i++)    {        cin>>peiodGroup[i].begin>>peiodGroup[i].end;    }    Sort(peiodGroup,len);    //output the sorted  peiodGroup    for (i=0;i<len;i++)    {        cout<<peiodGroup[i].begin<<","<<peiodGroup[i].end<<endl;    }    //    int dotCount=Count(peiodGroup,len);    cout<<dotCount<<endl;}