from itertools import combinations
def maximize_exhibition_value(N, artworks):
max_value = float('-inf')
# Try every possible non-empty subset
for r in range(1, N+1):
for subset in combinations(artworks, r):
sizes = [art[0] for art in subset]
values = [art[1] for art in subset]
A_max = max(sizes)
A_min = min(sizes)
S = sum(values)
current_value = S - (A_max - A_min)
max_value = max(max_value, current_value)
return max_value
# Input reading
N = int(input().strip())
artworks = []
for _ in range(N):
A, B = map(int, input().strip().split())
artworks.append((A, B))
# Calculate and print the result
result = maximize_exhibition_value(N, artworks)
print(result)
