void reverseWords(string &s) {
int i=0, j=0, wordStart=0; // i: index to scan the origin string; j: index to create the result
int len=s.length();
bool firstWord=true;
while (true) {
while (i<len && s[i] == ' ') i++; // skip spaces in front of the word
if (i==len) break;
if (firstWord) firstWord = false; // add one space between words
else s[j++] = ' ';
wordStart=j;
while (i<len && s[i]!=' ') {s[j]=s[i]; j++; i++;}
reverseword(s, wordStart, j-1); // reverse letters in each word
}
s.resize(j); // resize result string
reverseword(s, 0, j-1); // reverse whole string
}
void Solution::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++; // skip spaces in front of the word
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); // reverse word in place
wordcount++;
}
s.resize(j); // resize result string
reverseword(s,0,j-1); // reverse whole string
}
