LintCode - Backpack

class Solution {
public:
    /**
     * @param m: An integer m denotes the size of a backpack
     * @param A: Given n items with size A[i]
     * @return: The maximum size
     */
    int backPack(int m, vector<int> A) {
        // write your code here
        vector<int> result(m+1, 0);
        for (int i = 0; i < A.size(); i++) {
            for (int j = m; j >= A[i]; j--) {
                result[j] = max(result[j], result[j-A[i]] + A[i]);
            }
        }
        return result[m];
    }
};