edaBit-coding-challenges/camelCase----snake-case/code.cpp

/*  Create two functions toCamelCase() and toSnakeCase() that each take 
 *  a single string and convert it into either camelCase or snake_case. 
 *  If you're not sure what these terms mean, check the Resources tab above.
 */
//  rule 1, check for capitals
//  rule 2, check for underscore
std::string toSnakeCase(std::string str) {
	for(int i = 0;i<str.size();i++){
		//  insert an underscore before the uppercase
		if(isupper(str[i])){
			//  set uppercase to lowercase 
			str[i]=tolower(str[i]);
			str.insert(str.begin()+i,'_');
		}
	}
	return str;
}

std::string toCamelCase(std::string str) {
	int p;
	//  find underscore in string
	while(std::string::npos != (p = str.find('_'))){
		//  capitalize character after underscore
			if(str.size() != (p+1)){
				str[p+1]=toupper(str[p+1]);
			}
		//  remove underscore
			str.erase(p,1);
	}
	return str;
}