2315-CountAsterisks.go

package main

// 2315. Count Asterisks
// You are given a string s, where every two consecutive vertical bars '|' are grouped into a pair. 
// In other words, the 1st and 2nd '|' make a pair, the 3rd and 4th '|' make a pair, and so forth.

// Return the number of '*' in s, excluding the '*' between each pair of '|'.

// Note that each '|' will belong to exactly one pair.

// Example 1:
// Input: s = "l|*e*et|c**o|*de|"
// Output: 2
// Explanation: The considered characters are underlined: "l|*e*et|c**o|*de|".
// The characters between the first and second '|' are excluded from the answer.
// Also, the characters between the third and fourth '|' are excluded from the answer.
// There are 2 asterisks considered. Therefore, we return 2.

// Example 2:
// Input: s = "iamprogrammer"
// Output: 0
// Explanation: In this example, there are no asterisks in s. Therefore, we return 0.

// Example 3:
// Input: s = "yo|uar|e**|b|e***au|tifu|l"
// Output: 5
// Explanation: The considered characters are underlined: "yo|uar|e**|b|e***au|tifu|l". There are 5 asterisks considered. Therefore, we return 5.

// Constraints:
//     1 <= s.length <= 1000
//     s consists of lowercase English letters, vertical bars '|', and asterisks '*'.
//     s contains an even number of vertical bars '|'.

import "fmt"

func countAsterisks(s string) int {
    res, flag := 0, false
    for _, v := range s {
        if v == '|' {
            flag = !flag
        }
        if !flag && v == '*' {
            res++
        }
    }
    return res
}

func main() {
    // Example 1:
    // Input: s = "l|*e*et|c**o|*de|"
    // Output: 2
    // Explanation: The considered characters are underlined: "l|*e*et|c**o|*de|".
    // The characters between the first and second '|' are excluded from the answer.
    // Also, the characters between the third and fourth '|' are excluded from the answer.
    // There are 2 asterisks considered. Therefore, we return 2.
    fmt.Println(countAsterisks("l|*e*et|c**o|*de|")) // 2
    // Example 2:
    // Input: s = "iamprogrammer"
    // Output: 0
    // Explanation: In this example, there are no asterisks in s. Therefore, we return 0.
    fmt.Println(countAsterisks("iamprogrammer")) // 0
    // Example 3:
    // Input: s = "yo|uar|e**|b|e***au|tifu|l"
    // Output: 5
    // Explanation: The considered characters are underlined: "yo|uar|e**|b|e***au|tifu|l". There are 5 asterisks considered. Therefore, we return 5.
    fmt.Println(countAsterisks("yo|uar|e**|b|e***au|tifu|l")) // 5
}