# Reverse Words In A String Problem

## Description

LeetCode Problem 151.

Given an input string s, reverse the order of the words.

A word is defined as a sequence of non-space characters. The words in s will be separated by at least one space.

Return a string of the words in reverse order concatenated by a single space.

Note that s may contain leading or trailing spaces or multiple spaces between two words. The returned string should only have a single space separating the words. Do not include any extra spaces.

Example 1:

``````1
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Input: s = "the sky is blue"
Output: "blue is sky the"
``````

Example 2:

``````1
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Input: s = "  hello world  "
Output: "world hello"
``````

Example 3:

``````1
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Input: s = "a good   example"
Output: "example good a"
Explanation: You need to reduce multiple spaces between two words to a single space in the reversed string.
``````

Example 4:

``````1
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Input: s = "  Bob    Loves  Alice   "
Output: "Alice Loves Bob"
``````

Example 5:

``````1
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Input: s = "Alice does not even like bob"
Output: "bob like even not does Alice"
``````

Constraints:

• 1 <= s.length <= 10^4
• s contains English letters (upper-case and lower-case), digits, and spaces ‘ ‘.
• There is at least one word in s.

## Sample C++ Code

``````1
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class Solution {
public:
void reverseword(string &s, int i, int j){
while(i<j){
char t=s[i];
s[i++]=s[j];
s[j--]=t;
}
}

void reverseWords(string &s) {
int i=0, j=0;
int l=0;
int len=s.length();
int wordcount=0;

while(true){
while(i<len && s[i] == ' ') i++;
if(i==len) break;
if(wordcount) s[j++]=' ';
l=j;
while(i<len && s[i] != ' ') {s[j]=s[i]; j++; i++;}
reverseword(s,l,j-1);
wordcount++;

}

s.resize(j);
reverseword(s,0,j-1);
}
};
``````