{ "data": { "question": { "questionId": "677", "questionFrontendId": "677", "boundTopicId": null, "title": "Map Sum Pairs", "titleSlug": "map-sum-pairs", "content": "
Design a map that allows you to do the following:
\n\nImplement the MapSum
class:
MapSum()
Initializes the MapSum
object.void insert(String key, int val)
Inserts the key-val
pair into the map. If the key
already existed, the original key-value
pair will be overridden to the new one.int sum(string prefix)
Returns the sum of all the pairs' value whose key
starts with the prefix
.\n
Example 1:
\n\n\nInput\n["MapSum", "insert", "sum", "insert", "sum"]\n[[], ["apple", 3], ["ap"], ["app", 2], ["ap"]]\nOutput\n[null, null, 3, null, 5]\n\nExplanation\nMapSum mapSum = new MapSum();\nmapSum.insert("apple", 3); \nmapSum.sum("ap"); // return 3 (apple = 3)\nmapSum.insert("app", 2); \nmapSum.sum("ap"); // return 5 (apple + app = 3 + 2 = 5)\n\n\n
\n
Constraints:
\n\n1 <= key.length, prefix.length <= 50
key
and prefix
consist of only lowercase English letters.1 <= val <= 1000
50
calls will be made to insert
and sum
.Compiled with clang 11
using the latest C++ 17 standard.
Your code is compiled with level two optimization (-O2
). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
\"], \"java\": [\"Java\", \" OpenJDK 17
. Java 8 features such as lambda expressions and stream API can be used.
Most standard library headers are already included automatically for your convenience.
\\r\\nIncludes Pair
class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.
Python 2.7.12
.
Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.
\\r\\n\\r\\nFor Map/TreeMap data structure, you may use sortedcontainers library.
\\r\\n\\r\\nNote that Python 2.7 will not be maintained past 2020. For the latest Python, please choose Python3 instead.
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using the gnu99 standard.
Your code is compiled with level one optimization (-O1
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Most standard library headers are already included automatically for your convenience.
\\r\\n\\r\\nFor hash table operations, you may use uthash. \\\"uthash.h\\\" is included by default. Below are some examples:
\\r\\n\\r\\n1. Adding an item to a hash.\\r\\n
\\r\\nstruct hash_entry {\\r\\n int id; /* we'll use this field as the key */\\r\\n char name[10];\\r\\n UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n\\r\\n\\r\\n\\r\\n
2. Looking up an item in a hash:\\r\\n
\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n\\r\\n\\r\\n\\r\\n
3. Deleting an item in a hash:\\r\\n
\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n\\r\\n\"], \"csharp\": [\"C#\", \"\\r\\n\\r\\n
Your code is compiled with debug flag enabled (/debug
).
Node.js 16.13.2
.
Your code is run with --harmony
flag, enabling new ES6 features.
lodash.js library is included by default.
\\r\\n\\r\\nFor Priority Queue / Queue data structures, you may use datastructures-js/priority-queue and datastructures-js/queue.
\"], \"ruby\": [\"Ruby\", \"Ruby 3.1
Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms
\"], \"swift\": [\"Swift\", \"Swift 5.5.2
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Go 1.17.6
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Support https://godoc.org/github.com/emirpasic/gods library.
\"], \"python3\": [\"Python3\", \"Python 3.10
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Most libraries are already imported automatically for your convenience, such as array, bisect, collections. If you need more libraries, you can import it yourself.
\\r\\n\\r\\nFor Map/TreeMap data structure, you may use sortedcontainers library.
\"], \"scala\": [\"Scala\", \"Scala 2.13.7
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Kotlin 1.3.10
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Rust 1.58.1
Supports rand v0.6\\u00a0from crates.io
\"], \"php\": [\"PHP\", \"PHP 8.1
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With bcmath module
\"], \"typescript\": [\"Typescript\", \"TypeScript 4.5.4, Node.js 16.13.2
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Your code is run with --harmony
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lodash.js library is included by default.
\"], \"racket\": [\"Racket\", \"Run with Racket 8.3
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