Maximum Total Discount

You are given a list of n items. Each item is represented by its price and discount. A user is allowed to purchase any subset of these items, and the total discount a user can receive is the sum of discounts from the purchased items.

Since discounts are always non‐negative in this problem, the optimal strategy is straightforward: the maximum achievable total discount is simply the sum of the discounts of all items. Formally, if the discount for the i-th item is \(d_i\), then the maximum total discount is given by:

\(\text{Total Discount} = \sum_{i=1}^{n} d_i\)

Your task is to compute and print this total discount. Note that if n is zero, then there are no items and the output should be 0.

inputFormat

The input is read from stdin and is in the following format:

• The first line contains an integer n, the number of items.
• The next n lines each contain two space-separated integers, representing price and discount respectively.

If n equals 0, no additional lines follow.

outputFormat

Output a single integer to stdout which represents the maximum total discount achievable.

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210