©TCP-tryC++

#include <iostream>
#include <string>
using namespace std;

int main(void)
{
	string str1 = "C++ is very nice!";
	string str2 = "nice";
	string str3 = "awesome";
	
	string::size_type index = str1.find(str2);
	if (index != string::npos)
	{
		str1.replace(index, str2.length(), str3);
	}
		
	cout << str1;
	return 0;
}