hdoj 1058 Humble Numbers(dp)

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

st[i]=min{st[a]*2,st[b]*3,st[c]*5,st[d]*7}

View Code

 1 #include <iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 using namespace std;
 5 int main()
 6 {
 7     long int n;
 8     long int st[5850];
 9     long int a=1,b=1,c=1,d=1,small,i;
10     st[1]=1;
11     for(i=2;i<5850;i++)
12     {
13         small=st[a]*2;
14         if(small>st[b]*3)
15         small=st[b]*3;
16         if(small>st[c]*5)
17         small=st[c]*5;
18         if(small>st[d]*7)
19         small=st[d]*7;
20         if(small==st[a]*2)
21         a++;
22         if(small==st[b]*3)
23         b++;
24         if(small==st[c]*5)
25         c++;
26         if(small==st[d]*7)
27         d++;
28         st[i]=small;
29     }
30     while(scanf("%ld",&n))
31     {
32         if(n==0)
33         break;
34         if(n%10==1&&n%100!=11)
35         printf("The %ldst humble number is %ld.\n",n,st[n]);
36         else if(n%10==2&&n%100!=12)
37         printf("The %ldnd humble number is %ld.\n",n,st[n]);
38         else if(n%10==3&&n%100!=13)
39         printf("The %ldrd humble number is %ld.\n",n,st[n]);
40         else
41         printf("The %ldth humble number is %ld.\n",n,st[n]);
42     }
43     return 0;
44 }