codeforces 617B Chocolate

 1 #include<iostream>
 2 #include<string>
 3 #include<algorithm>
 4 #include<cstdlib>
 5 #include<cstdio>
 6 #include<set>
 7 #include<map>
 8 #include<vector>
 9 #include<cstring>
10 #include<stack>
11 #include<cmath>
12 #include<queue>
13 #include <bits/stdc++.h>
14 using namespace std;
15 #define INF 0x3f3f3f3f
16 #define ll long long
17 #define clc(a,b) memset(a,b,sizeof(a))
18 const int maxn=1000000;
19 const int mod=1e9+7;
20 
21 ll dp[110];
22 int n;
23 int a[110];
24 
25 int main()
26 {
27     while(~scanf("%d",&n))
28     {
29         clc(dp,0);
30         for(int i=0;i<n;i++)
31             cin>>a[i];
32             dp[0]=1;
33         for(int i=1;i<=n;i++)
34         {
35             ll s=0;
36             for(int j=i-1;j>=0;j--)
37             {
38                 s+=a[j];
39                 if(s==1)
40                     dp[i]+=dp[j];
41             }
42         }
43         cout<<dp[n]<<endl;
44     }
45     return 0;
46 }