{ "data": { "question": { "questionId": "726", "questionFrontendId": "726", "categoryTitle": "Algorithms", "boundTopicId": 1879, "title": "Number of Atoms", "titleSlug": "number-of-atoms", "content": "

Given a string formula representing a chemical formula, return the count of each atom.

\n\n

The atomic element always starts with an uppercase character, then zero or more lowercase letters, representing the name.

\n\n

One or more digits representing that element's count may follow if the count is greater than 1. If the count is 1, no digits will follow.

\n\n\n\n

Two formulas are concatenated together to produce another formula.

\n\n\n\n

A formula placed in parentheses, and a count (optionally added) is also a formula.

\n\n\n\n

Return the count of all elements as a string in the following form: the first name (in sorted order), followed by its count (if that count is more than 1), followed by the second name (in sorted order), followed by its count (if that count is more than 1), and so on.

\n\n

The test cases are generated so that all the values in the output fit in a 32-bit integer.

\n\n

 

\n

Example 1:

\n\n
\nInput: formula = "H2O"\nOutput: "H2O"\nExplanation: The count of elements are {'H': 2, 'O': 1}.\n
\n\n

Example 2:

\n\n
\nInput: formula = "Mg(OH)2"\nOutput: "H2MgO2"\nExplanation: The count of elements are {'H': 2, 'Mg': 1, 'O': 2}.\n
\n\n

Example 3:

\n\n
\nInput: formula = "K4(ON(SO3)2)2"\nOutput: "K4N2O14S4"\nExplanation: The count of elements are {'K': 4, 'N': 2, 'O': 14, 'S': 4}.\n
\n\n

 

\n

Constraints:

\n\n\n", "translatedTitle": "原子的数量", "translatedContent": "

给你一个字符串化学式 formula ，返回 每种原子的数量 。

\n\n

原子总是以一个大写字母开始，接着跟随 0 个或任意个小写字母，表示原子的名字。

\n\n

如果数量大于 1，原子后会跟着数字表示原子的数量。如果数量等于 1 则不会跟数字。

\n\n\n\n

两个化学式连在一起可以构成新的化学式。

\n\n\n\n

由括号括起的化学式并佐以数字（可选择性添加）也是化学式。

\n\n\n\n

返回所有原子的数量，格式为：第一个（按字典序）原子的名字，跟着它的数量（如果数量大于 1），然后是第二个原子的名字（按字典序），跟着它的数量（如果数量大于 1），以此类推。

\n\n

 

\n\n

示例 1：

\n\n
\n输入：formula = \"H2O\"\n输出：\"H2O\"\n解释：原子的数量是 {'H': 2, 'O': 1}。\n
\n\n

示例 2：

\n\n
\n输入：formula = \"Mg(OH)2\"\n输出：\"H2MgO2\"\n解释：原子的数量是 {'H': 2, 'Mg': 1, 'O': 2}。\n
\n\n

示例 3：

\n\n
\n输入：formula = \"K4(ON(SO3)2)2\"\n输出：\"K4N2O14S4\"\n解释：原子的数量是 {'K': 4, 'N': 2, 'O': 14, 'S': 4}。\n
\n\n

 

\n\n

提示：

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