Solution 3 – Two pointers
func reverseWords(s string) string {
// solution 3
/*
trim and split, use two pointers to keep swapping two word at ends
*/
s = strings.Trim(s," ")
sWords:= strings.Fields(s)
j:=len(sWords)-1
i:=0
for i<j{
sWords[i],sWords[j]=sWords[j],sWords[i]
i++
j--
}
return strings.Join(sWords," ")
}
Solution 2 – Without array of words
func reverseWords(s string) string {
// solution 2
/*
operate on string and create new string
*/
var res string
var sawSpace bool
var word []byte
for i:=0;i<len(s);i++{
if s[len(s)-i-1]==32 && sawSpace {
// repeated space
continue
}
if s[len(s)-i-1]==32{
sawSpace=true
res+=reverse(word)+" "
word=nil
} else {
sawSpace=false
word=append(word,s[len(s)-i-1])
}
}
res+=reverse(word)+" "
return strings.Trim(res," ")
}
func reverse(s []byte) string{
var res []byte
for i:=range s{
res=append(res,s[len(s)-i-1])
}
return string(res)
}
Solution 1 –
func reverseWords(s string) string {
// solution 1
/*
trim spaces at ends, split by space, start from last index, add reverse+space if not empty string
join and return
*/
s = strings.Trim(s," ")
arr:= strings.Split(s," ")
var res string
for i:=len(arr)-1;i>-1;i--{
if arr[i]!=""{
res+=arr[i]+" "
}
}
return strings.Trim(res," ")
}
