HDU 1058 Humble Numbers

题目：http://acm.hdu.edu.cn/showproblem.php?pid=1058

#include <iostream>
#include <cmath>
#include <set>
using namespace std;
int main(int argc, const char *argv[])
{
    int p2,p3,p5,p7;//记录2,3,5,7
    set<int> dp;
    dp.insert(1);
    while(dp.size()<5843)
    {
        int a[4]={
            2,3,5,7
        };
        for(int k=0;k<4;k++)
        {
            for (set<int>::iterator i=dp.begin(); i!=dp.end(); ++i)
            {
                int t = *i;
            //    cout<<*dp.rbegin();
                if(t * a[k]>2000000000 ) break;
                dp.insert(t * a[k]);
                //cout<<t * a[k]<<endl;
            }
            //cout<<k<<"容量"<<dp.size()<<"最大"<<*dp.rbegin()<<endl;
        }
    }
    int ans[5843]={0};
    int n=0;
    for (set<int>::iterator i=dp.begin(); i!=dp.end(); ++i)
    {
        ans[n]=*i;
        n++;
    }
    while(cin>>n&&n)
    {
        if(n%10==1&&n%100!=11)
        {
            printf("The %dst ",n);
        }
        else if(n%10==2&&n%100!=12)
        {
            printf("The %dnd ",n);
        }
        else if(n%10==3&&n%100!=13)
        {
            printf("The %drd ",n);
        }
        else printf("The %dth ",n);
        printf("humble number is %d.
",ans[n]);
    }
    return 0;
}