Dynamic Programming Question: maximize profit for wine sale

/**
 * you have a collection of N wines placed next to each other on a shelf. For
 * simplicity, let's number the wines from left to right as they are standing on
 * the shelf with integers from 1 to N, respectively. The price of the i-th wine
 * is pi (prices of different wines can be different).
 * Because the wines get better every year, supposing today is the year 1, on
 * year y the price of the i-th wine will be y*pi, i.e. y-times more than the
 * current year.
 * what is the maximum profit you can get, if you sell the wines in optimal order.
 * So for example, if the prices of the wines are (in the order as they are
 * placed on the shelf, from left to right): p1=1, p2=4, p3=2, p4=3.
 *
 */
public class DP1 {
    int p[] = null;
    int cache[][];
   
    public DP1(){
        p = new int[100];
        cache = new int[100][100];
        for(int i=0; i<100; i++)
            for(int j=0; j<100; j++)
                cache[i][j] = -1;
    }
   
    public DP1(int N){
        p = new int[N];
        cache = new int[N][N];
        for(int i=0; i<N; i++)
            for(int j=0; j<N; j++)
                cache[i][j] = -1;
    }
   
    /**
     * Description: Backtracking function to find maximum profit.
     * @param year : starts from 1 to N-1
     * @param be : beginning of price array
     * @param en : end of price array
     * @return : maximized profit
     */
    public int maxProfit(int year, int be, int en){
        if(be>en)
            return 0;
        return Math.max((this.maxProfit(year+1, be+1, en)+year*this.p[be]),(this.maxProfit(year+1, be, en-1) + year*p[en]));
    }
   
    /*
     * Dynamic Programming Approach
     */
    public int maxDPProfit(int be, int en){
        if(be > en)
            return 0;
       
        if(cache[be][en] != -1)
            return cache[be][en];
       
        int year = this.p.length - (en-be+1) + 1;
        cache[be][en] = Math.max((this.maxDPProfit(be+1, en) + year*p[be]),(this.maxDPProfit(be, en-1)+year*p[en]));
        return cache[be][en];
    }
   
    public static void main(String args[]){
        DP1 dp = new DP1();
        int p[] = new int[]{1,4,2,3};
        dp.p = p;
        int profit = dp.maxProfit(1, 0, 3);
        System.out.println("Profit: " + profit);
        //DP
        int dpprofit = dp.maxDPProfit(0, 3);
        System.out.println("DP Profit: " + dpprofit);
    }
}

#output:

Profit: 29

DP Profit: 29