java 数组分割、合并方法

    public static int[] slice(int[] arr, int start, int end) {
        int len = end - start + 1;
        int[] ts = new int[len];
        int offset = 0;
        while (offset < len) {
            ts[offset] = arr[offset + start];
            offset++;
        }
        return ts;
    }

    public static int[] concate(int[]... arr) {
        int total = 0;
        int[] result;
        for (int i = 0, len = arr.length; i < len; i++) {
            total += arr[i].length;
        }
        result = new int[total];
        int index = 0;
        for (int i = 0, len = arr.length; i < len; i++) {
            int[] ele = arr[i];
            for (int i1 : ele) {
                result[index++] = i1;
            }
        }
        return result;
    }