Backpack

public class Solution {
    public int backPack(int m, int[] A) {
        // write your code here
        if (A == null || A.length == 0) return 0;

        int[] size = new int[m + 1];
        //previous i items fill size j
        for (int i = 1; i <= A.length; i++) {
            for (int j = m; j >= 0; j--) {
                if (j >= A[i-1]) {
                    size[j] = Math.max(size[j], size[j-A[i-1]] + A[i-1]);
                }
            }
        }
        return size[m];
    }
}

public class Solution {
    /**
     * @param m: An integer m denotes the size of a backpack
     * @param A: Given n items with size A[i]
     * @return: The maximum size
     */
    public int backPack(int m, int[] A) {
        // write your code here
        if (A == null || A.length == 0) return 0;

        int[][] size = new int[A.length + 1][m + 1];
        //previous i items fill size j

        for (int i = 1; i <= A.length; i++) {
            for (int j = 1; j <= m; j++) {
                if (j >= A[i-1]) {
                    size[i][j] = Math.max(size[i-1][j], size[i-1][j-A[i-1]] + A[i-1]);
                } else {
                    size[i][j] = size[i-1][j];
                }
            }
        }
        return size[A.length][m];
    }
}