Consolidate Data Records

You are given a list of records. Each record consists of a name (a string) and a value (an integer). Your task is to consolidate these records by summing the values for records with the same name.

If the input indicates a null list, the result should be an empty dictionary.

Formally, if the input contains records \(\{(name_i, value_i)\}_{i=1}^{n}\), you should output a dictionary \(D\) where \[ D[name] = \sum_{i: name_i = name} value_i \] for each unique name in the input.

inputFormat

The input is read from standard input (stdin) in the following format:

1. The first line contains an integer n.
2. If n == -1, it indicates that the input is null and should be treated as an empty list.
3. If n >= 0, then the next n lines each contain a record. Each record consists of a string and an integer separated by a space, representing name and value respectively.

outputFormat

Output to standard output (stdout) the consolidated dictionary in JSON format. The dictionary should map each unique name to the sum of its values. If there is no record (i.e. the input is null or empty), output an empty dictionary {}.

Note: The order of keys in the output does not matter.

3
apple 10
banana 5
apple 3

{"apple": 13, "banana": 5}