A factory conveyor belt is divided into n consecutive load-bearing segments; the i-th segment currently carries a load of weight w_i. For quality auditing, the plant's monitoring system looks at every contiguous run of one or more segments — there are n(n+1)/2 such runs in total, including every single segment on its own and the run spanning the entire belt — and computes the total weight carried across that run. The plant's audit signature is obtained by taking the bitwise OR of the totals of every one of these runs. Given the segment weights, compute the audit signature.

Input format

• Line 1: a single integer n — the number of conveyor segments.
• Line 2: n space-separated integers w1, w2, ..., wn — the weight carried by each segment, in order along the belt.

Output format

Print a single integer: the bitwise OR, taken over every contiguous run of one or more segments, of that run's total weight.

Constraints

• 1 <= n <= 3000
• 0 <= w_i <= 10^9

3
1 2 4

7

2
5 5

15