Reversing words in a String

Sample input String = "Ajitesh is a good boy"

Sample output String="boy good a is Ajitesh"

string wordReverse(string str) {     int i = str.length() - 1;     int start, end = i + 1;     string result = "";            while(i >= 0)     {         if(str[i] == ' ')         {             start = i + 1;             while(start != end)                 result += str[start++];                            result += ' ';                            end = i;         }         i--;     }     start = 0;     while(start != end)         result += str[start++];            return result; }    // main code int main() {     string str = "Ajitesh is a good boy";            cout << wordReverse(str);            return 0; }