Java Max Slice Sum
public class Solution {
    public static int maxSliceSum(int[] a) {
        long tmp = Long.MIN_VALUE;
        long max = Long.MIN_VALUE;

        for (int v : a) {
            tmp = Math.max(tmp + v, v);
            max = Math.max(max, tmp);
        }

        return (int) max;
    }
}

This is a Kadane-style scan: keep the best running sum and the best overall sum while moving once through the array.