forked from spring1843/go-dsa
-
Notifications
You must be signed in to change notification settings - Fork 0
/
reverse_vowels.go
45 lines (40 loc) · 801 Bytes
/
reverse_vowels.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
package strings
import "errors"
var (
stack []string
vowels = map[string]bool{
`a`: true,
`e`: true,
`o`: true,
`i`: true,
`u`: true,
}
// ErrPopStack is returned when the stack is empty.
ErrPopStack = errors.New("can not Pop on an empty stack")
)
// ReverseVowels solves the problem in O(n) time and O(n) space.
func ReverseVowels(str string) (string, error) {
stack = []string{}
reversed := ""
for _, r := range str {
if _, ok := vowels[string(r)]; ok {
push(string(r))
}
}
for _, r := range str {
if _, ok := vowels[string(r)]; ok {
reversed += pop()
continue
}
reversed += string(r)
}
return reversed, nil
}
func push(v string) {
stack = append(stack, v)
}
func pop() string {
tmp := stack[len(stack)-1]
stack = stack[:len(stack)-1]
return tmp
}