Change the Signs

You are given a sequence of integers $A_1, A_2, \dots, A_N$. You should choose an arbitrary (possibly empty) subsequence of $A$ and multiply each element of this subsequence by $-1$. The resulting sequence should satisfy the following condition: the sum of elements of any **contiguous** subsequence with length greater than 1 is strictly positive. You should minimise the sum of elements of the re