Problem
JSON is the text format most programs use to exchange data. A JSON object is written as {"key": "value", ...}.
Given matching lists of keys and values (all text), build the JSON object string in this exact format:
- Start with
{and end with}. - Write each pair as
"key": "value", in the given order, separated by,(comma and space). - Inside a string, write a backslash
\as\\and a double quote"as\". Other characters stay as they are.
Implement json_object_string(keys, values).
Input
keys, values: Lists of the same length.
Output
Return the JSON text. An empty object is {}.
Constraints
0 ≤ number of pairs ≤ 100
Keys and values have at most 50 printable characters
Examples
Input:
keys = ["name", "city"]
values = ["Ada", "London"]
Expected output:
expected = "{\"name\": \"Ada\", \"city\": \"London\"}"Input:
std::vector<std::string> keys = {"name", "city"};
std::vector<std::string> values = {"Ada", "London"};
Expected output:
std::string expected = "{\"name\": \"Ada\", \"city\": \"London\"}";Input:
string[] keys = new string[] {"name", "city"};
string[] values = new string[] {"Ada", "London"};
Expected output:
string expected = "{\"name\": \"Ada\", \"city\": \"London\"}";Explanation
Each pair becomes "key": "value": {"name": "Ada", "city": "London"}.
Input:
keys = ["quote"]
values = ["say \"hi\""]
Expected output:
expected = "{\"quote\": \"say \\\"hi\\\"\"}"Input:
std::vector<std::string> keys = {"quote"};
std::vector<std::string> values = {"say \"hi\""};
Expected output:
std::string expected = "{\"quote\": \"say \\\"hi\\\"\"}";Input:
string[] keys = new string[] {"quote"};
string[] values = new string[] {"say \"hi\""};
Expected output:
string expected = "{\"quote\": \"say \\\"hi\\\"\"}";Explanation
The quotes inside the value are escaped with a backslash: {"quote": "say \"hi\""}.
How to approach it
Try on your own first, then open one hint at a time.
Hint 1
Build each "key": "value" pair separately, then join them.
Hint 2
Escape backslashes before quotes so you don't escape your own escapes.
Hint 3
An empty input still needs the braces: {}.
Expected complexity
O(total length) time, O(total length) extra space
References
This challenge is adapted for CodeUtility. Follow the statement and constraints above.