"""

後ろから見ていく？

"""

N = int(input())


AB = []
for i in range(N):
    A,B = map(int,input().split())
    AB.append( (A,B) )

dp = [float("-inf")] * (N+1)
dp[0] = 0

for a,b in reversed(AB):

    ndp = [float("-inf")] * (N+1)

    for i in range(N+1):

        # a
        ndp[i] = max(ndp[i], dp[i] + a * i)
        # b
        if i != N:
            ndp[i+1] = max(ndp[i+1], dp[i] + b)

    dp = ndp

print (max(dp))