How to captalize and title a string - c++

Question

If I was given a string, I need to either capitalize or title the string. For example:

Answer 1

There are some problems with your code. Here is the modified version of your code that works fine. Here:
std::string Capitalize(const std::string &str) {
std::string Ret;
for (int i = 0; i < str.length(); i++){
char c = str[i];
if (i == 0){
Ret += toupper(c);
}
else if (i != 0){
Ret += (tolower(c));
}
}
return Ret;}
Condition in for loop needs to be str.length() not Ret.length() and here :
std::string Title(const std::string &str) {
std::string Ret;
int i=0;
for (int i=0;i<str.size();i++) {
if(!(i==0 && str[i]==' '))
Ret += tolower(str[i]);
}
int size = Ret.length();
for (int i = 0; i < size; i++) {
if (i==0 || Ret[i - 1] == ' ')
{
Ret[i] = toupper(Ret[i]);
}
}
return Ret;}
Check if i is 0 to prevent out of range access to string.

Answer 2

Use a stringstream to first split all words, so that you can do this easily with a vector. This is an implementation of the Title function:
std::string Title(const std::string &str) {
std::vector<string>words;
words.clear();
std::string res = str, std::ans = "";
// It's better to pass the string AFTER you convert it all lowercase. Or you can only work with the capitalized characters:
for(int i = 0; i < res.size(); ++i){
if(res[i] >= 'A' && res[i] <= 'Z'){
res[i] = tolower(res[i]);
}
}
istringstream ss(res); // We push the modified string into a stringstream.
do{
res = "";
ss >> res;
words.push_back(res); // We split the string at " " and push each word in the vector.
} while(ss)
for(int i = 0; i < words.size(); ++i){
res = words[i];
res[0] = toUpper(res[0]); // For each word, we capitalize it
ans += res; // We add the word to our return string.
if(i < words.size() - 1){
ans += " "; // If this is not the last word, add a space
}
}
return ans;
}
As for the capitalization, you can do something like this:
std::string Capitalize(const std::string &&str){
std::string res = str;
res[0] = toupper(res[0]);
for(int i = 1; i < res.size(); ++i){
if(res[i] >= 'A' && res[i] <= 'Z'){
res[i] = tolower(res[i]); // converting if only an uppercase character.
}
}
return res; // If you pass a reference, the original will be modified so no return required.
}