http://acm.hdu.edu.cn/showproblem.php?pid=2006

 1 #include<iostream>
 2 #include<stdio.h>
 3 #include<math.h>
 4 #include<queue>
 5 #include<stack>
 6 #include<algorithm>
 7 #define PI 3.1415927
 8 using namespace std;
 9 
10 int main()
11 {
12     int a[20],n,i,sum;
 
13     while(~scanf("%d",&n))
14     {
15         sum=1;
16         for(i=0;i<n;i++)
17         {
18             scanf("%d",&a[i]);
19             if(a[i]%2!=0)
20             {
21                 sum*=a[i];
22             }
23         }
24         printf("%d\n",sum);
25     }
26 
27     return
 
 0;
28 }

hdu 2006