{ "data": { "question": { "questionId": "2154", "questionFrontendId": "2027", "categoryTitle": "Algorithms", "boundTopicId": 1026585, "title": "Minimum Moves to Convert String", "titleSlug": "minimum-moves-to-convert-string", "content": "
You are given a string s
consisting of n
characters which are either 'X'
or 'O'
.
A move is defined as selecting three consecutive characters of s
and converting them to 'O'
. Note that if a move is applied to the character 'O'
, it will stay the same.
Return the minimum number of moves required so that all the characters of s
are converted to 'O'
.
\n
Example 1:
\n\n\nInput: s = "XXX"\nOutput: 1\nExplanation: XXX -> OOO\nWe select all the 3 characters and convert them in one move.\n\n\n
Example 2:
\n\n\nInput: s = "XXOX"\nOutput: 2\nExplanation: XXOX -> OOOX -> OOOO\nWe select the first 3 characters in the first move, and convert them to\n\n'O'
.\nThen we select the last 3 characters and convert them so that the final string contains all'O'
s.
Example 3:
\n\n\nInput: s = "OOOO"\nOutput: 0\nExplanation: There are no\n\n'X's
ins
to convert.\n
\n
Constraints:
\n\n3 <= s.length <= 1000
s[i]
is either 'X'
or 'O'
.给你一个字符串 s
,由 n
个字符组成,每个字符不是 'X'
就是 'O'
。
一次 操作 定义为从 s
中选出 三个连续字符 并将选中的每个字符都转换为 'O'
。注意,如果字符已经是 'O'
,只需要保持 不变 。
返回将 s
中所有字符均转换为 'O'
需要执行的 最少 操作次数。
\n\n
示例 1:
\n\n\n输入:s = \"XXX\"\n输出:1\n解释:XXX -> OOO\n一次操作,选中全部 3 个字符,并将它们转换为 'O' 。
\n
\n\n示例 2:
\n\n\n输入:s = \"XXOX\"\n输出:2\n解释:XXOX -> OOOX -> OOOO\n第一次操作,选择前 3 个字符,并将这些字符转换为\n\n'O'
。\n然后,选中后 3 个字符,并执行转换。最终得到的字符串全由字符'O'
组成。
示例 3:
\n\n\n输入:s = \"OOOO\"\n输出:0\n解释:s 中不存在需要转换的 'X' 。
\n
\n\n\n\n
提示:
\n\n3 <= s.length <= 1000
s[i]
为 'X'
或 'O'
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