{ "data": { "question": { "questionId": "473", "questionFrontendId": "473", "categoryTitle": "Algorithms", "boundTopicId": 1208, "title": "Matchsticks to Square", "titleSlug": "matchsticks-to-square", "content": "

You are given an integer array matchsticks where matchsticks[i] is the length of the ith matchstick. You want to use all the matchsticks to make one square. You should not break any stick, but you can link them up, and each matchstick must be used exactly one time.

\n\n

Return true if you can make this square and false otherwise.

\n\n

 

\n

Example 1:

\n\"\"\n
\nInput: matchsticks = [1,1,2,2,2]\nOutput: true\nExplanation: You can form a square with length 2, one side of the square came two sticks with length 1.\n
\n\n

Example 2:

\n\n
\nInput: matchsticks = [3,3,3,3,4]\nOutput: false\nExplanation: You cannot find a way to form a square with all the matchsticks.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "火柴拼正方形", "translatedContent": "

你将得到一个整数数组 matchsticks ，其中 matchsticks[i] 是第 i 个火柴棒的长度。你要用 所有的火柴棍 拼成一个正方形。你 不能折断 任何一根火柴棒，但你可以把它们连在一起，而且每根火柴棒必须 使用一次 。

\n\n

如果你能使这个正方形，则返回 true ，否则返回 false 。

\n\n

 

\n\n

示例 1:

\n\n

\n\n
\n输入: matchsticks = [1,1,2,2,2]\n输出: true\n解释: 能拼成一个边长为2的正方形，每边两根火柴。\n
\n\n

示例 2:

\n\n
\n输入: matchsticks = [3,3,3,3,4]\n输出: false\n解释: 不能用所有火柴拼成一个正方形。\n
\n\n

 

\n\n

提示:

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