text: #include <iostream>
  #include <string>
  
  int main()
  {
    std::string str{ "I saw a red car yesterday." };
  
    // replace "red" with "blue"
    // "red" is 3 characters starting at position 8
    str.replace(8, 3, "blue");
  
    std::cout << str << '\n'; // I saw a blue car yesterday.
  
    return 0;
  }
  