Kadane's algorithm, along with finding sum-array bounds

kadane.py

a = [3, -1, 5, -12, 0, -6, 3, 5, -12]


end_seq = []
max_ending_here = max_so_far = n = 0
for i in range(len(a)):
    if max_ending_here + a[i] > a[i]:
        max_ending_here = max_ending_here + a[i]
    else:
        max_ending_here = a[i]
        n = i
    
    if max_ending_here > max_so_far:
        max_so_far = max_ending_here
        del end_seq[:]
        end_seq.append((n, i))

print(max_so_far, end_seq)