Formatted question description: https://leetcode.ca/all/520.html
520. Detect Capital (Easy)
Given a word, you need to judge whether the usage of capitals in it is right or not.
We define the usage of capitals in a word to be right when one of the following cases holds:
- All letters in this word are capitals, like "USA".
- All letters in this word are not capitals, like "leetcode".
- Only the first letter in this word is capital, like "Google".
Otherwise, we define that this word doesn’t use capitals in a right way.
Example 1:
Input: "USA" Output: True
Example 2:
Input: "FlaG" Output: False
Note: The input will be a non-empty word consisting of uppercase and lowercase latin letters.
Related Topics:
String
Solution 1.
// OJ: https://leetcode.com/problems/detect-capital/
// Time: O(N)
// Space: O(1)
class Solution {
public:
bool detectCapitalUse(string word) {
if (word.size() < 2) return true;
bool a = isupper(word[0]), b = isupper(word[1]), upper = a && b;
if (!a && b) return false;
for (int i = 2; i < word.size(); ++i) {
if (isupper(word[i]) > 0 != upper) return false;
}
return true;
}
};
Solution 2.
// OJ: https://leetcode.com/problems/detect-capital/
// Time: O(N)
// Space: O(1)
class Solution {
public:
bool detectCapitalUse(string word) {
int cnt = 0;
for (char c : word) cnt += isupper(c) > 0;
return !cnt || cnt == word.size() || cnt == 1 && isupper(word[0]);
}
};
Java
-
class Solution { public boolean detectCapitalUse(String word) { if (word == null) return false; int length = word.length(); if (length <= 1) return true; char c0 = word.charAt(0); boolean firstCapital = isCapital(c0); if (firstCapital) { char prevC = word.charAt(1); for (int i = 2; i < length; i++) { char curC = word.charAt(i); if (isCapital(prevC) ^ isCapital(curC)) return false; prevC = curC; } return true; } else { for (int i = 1; i < length; i++) { char c = word.charAt(i); if (isCapital(c)) return false; } return true; } } public boolean isCapital(char c) { return c >= 'A' && c <= 'Z'; } }
-
// OJ: https://leetcode.com/problems/detect-capital/ // Time: O(N) // Space: O(1) class Solution { public: bool detectCapitalUse(string word) { if (word.size() < 2) return true; bool a = isupper(word[0]), b = isupper(word[1]), upper = a && b; if (!a && b) return false; for (int i = 2; i < word.size(); ++i) { if (isupper(word[i]) > 0 != upper) return false; } return true; } };
-
import string class Solution(object): def detectCapitalUse(self, word): """ :type word: str :rtype: bool """ ud = set(string.uppercase) ld = set(string.lowercase) n = len(word) cap = 0 for c in word: if c in ud: cap += 1 if cap == n: return True if cap == 1 and word[0] in ud: return True return False if cap > 0 else True