n = int(input())
ls = [list(map(int, input().split())) for _ in range(n)]

dp = [[0] * (n + 1) for _ in range(n+1)]

for i in reversed(range(n)):
  for j in range(n-i):
    dp[i][j] = max(dp[i][j], dp[i+1][j]+ls[i][0]*j)
    dp[i][j+1] = max(dp[i][j+1], dp[i+1][j]+ls[i][1])

print(max(dp[0]))