2586-CountTheNumberOfVowelStringsInRange.go

package main

// 2586. Count the Number of Vowel Strings in Range
// You are given a 0-indexed array of string words and two integers left and right.
// A string is called a vowel string if it starts with a vowel character and ends with a vowel character where vowel characters are 'a', 'e', 'i', 'o', and 'u'.
// Return the number of vowel strings words[i] where i belongs to the inclusive range [left, right].

// Example 1:
// Input: words = ["are","amy","u"], left = 0, right = 2
// Output: 2
// Explanation: 
// - "are" is a vowel string because it starts with 'a' and ends with 'e'.
// - "amy" is not a vowel string because it does not end with a vowel.
// - "u" is a vowel string because it starts with 'u' and ends with 'u'.
// The number of vowel strings in the mentioned range is 2.

// Example 2:
// Input: words = ["hey","aeo","mu","ooo","artro"], left = 1, right = 4
// Output: 3
// Explanation: 
// - "aeo" is a vowel string because it starts with 'a' and ends with 'o'.
// - "mu" is not a vowel string because it does not start with a vowel.
// - "ooo" is a vowel string because it starts with 'o' and ends with 'o'.
// - "artro" is a vowel string because it starts with 'a' and ends with 'o'.
// The number of vowel strings in the mentioned range is 3.

// Constraints:
//     1 <= words.length <= 1000
//     1 <= words[i].length <= 10
//     words[i] consists of only lowercase English letters.
//     0 <= left <= right < words.length

import "fmt"

func vowelStrings(words []string, left int, right int) int {
    // 判断是否均元音字符
    isVowelCharacter := func (c byte) bool {
        // vowel characters are 'a', 'e', 'i', 'o', and 'u'.
        return c == 'a' || c == 'e' || c == 'i'  || c == 'o' || c == 'u' 
    }
    res := 0
    for i := left; i <= right; i++ {
        if isVowelCharacter(words[i][0]) && isVowelCharacter(words[i][len(words[i]) - 1]) {
            res++
        }
    }
    return res
}


func main() {
    // - "are" is a vowel string because it starts with 'a' and ends with 'e'.
    // - "amy" is not a vowel string because it does not end with a vowel.
    // - "u" is a vowel string because it starts with 'u' and ends with 'u'.
    fmt.Println(vowelStrings([]string{"are","amy","u"},0,2)) // 2
    // - "aeo" is a vowel string because it starts with 'a' and ends with 'o'.
    // - "mu" is not a vowel string because it does not start with a vowel.
    // - "ooo" is a vowel string because it starts with 'o' and ends with 'o'.
    // - "artro" is a vowel string because it starts with 'a' and ends with 'o'.
    // The number of vowel strings in the mentioned range is 3.
    // The number of vowel strings in the mentioned range is 2.
    fmt.Println(vowelStrings([]string{"hey","aeo","mu","ooo","artro"},1, 4)) // 3
}