ex9_44.cpp

//
//  ex9_44.cpp
//  Exercise 9.44
//
//  Created by XDXX on 4/17/15.
//  Copyright (c) 2015 XDXX. All rights reserved.
//
//  @Brief  Rewrite the previous function using an index and replace.
//  @See    9.43

#include <iostream>
#include <string>

using std::cout; using std::endl; using std::string;

void func(string &s, string const& oldVal, string const& newVal)
{
	for (size_t pos = 0; pos <= s.size() - oldVal.size();) {
		if (s[pos] == oldVal[0] && s.substr(pos, oldVal.size()) == oldVal) {
			s.replace(pos, oldVal.size(), newVal);
			pos += newVal.size();
		}
		else
			++pos;
	}
}

int main()
{
	string str{"To drive straight thru is a foolish, tho courageous act."};
   	func(str, "tho", "though");
  	func(str, "thru", "through");
	cout << str << endl;
	return 0;
}