#include <iostream>

 #include <cstring>

 using namespace std;

 const int INF = 0x3f3f3f3f;

 const int N = ;

 int a[N], sum[N], dp[N][N][N];

 int n, L, R;

 int dfs(int l, int r, int k)

 {

     if (l == r) return k ==  ?  : INF;

     if (r - l +  == k) return ;

     if (dp[l][r][k] != -) return dp[l][r][k];

     int ans = INF;

     if (k == )

     {

         for (int i = L; i <= R; i++)

             ans = min(ans, dfs(l, r, i) + sum[r] - sum[l - ]);

     }

     else

     {

         for (int i = ; i < r - l; i++)

             ans = min(ans, dfs(l, l + i, ) + dfs(l + i + , r, k - ));

     }

     return dp[l][r][k] = ans;

 }

 int main()

 {

     while (cin >> n >> L >> R)

     {

         memset(sum, , sizeof sum);

         memset(dp, -, sizeof dp);

         for (int i = ; i <= n; i++)

         {

             cin >> a[i];

             sum[i] = sum[i - ] + a[i];

         }

         int ans = dfs(, n, );

         cout << (ans == INF ?  : ans) << endl;

     }

     return ;

 }