update,

task1/_ref/Chapter02/helloworld.cpp

@@ -0,0 +1,19 @@
+#include <iostream>
+#include <iomanip>
+
+using namespace std;
+
+int main()
+{
+    std::cout << "Price list of a restaurant"<<endl;
+    std::cout << setw(20)
+        << setfill(' ')
+        << left
+        << "Cheese burger: "
+        << " $"
+        << setw(4)
+        << setfill(' ')
+        << right
+        << "14"
+        << endl;
+}

task1/_ref/Chapter03/helloworld.cpp

@@ -0,0 +1,45 @@
+#include <iostream>
+#include <fstream>
+#include <iomanip>
+#include <string>
+
+using namespace std;
+
+int main(){
+    //Declare variables
+    ifstream inFile;
+    ofstream outFile;
+    string burger_name, fries_name, icecream_name;
+    int burger_price, fries_price, icecream_price;
+    //Open the input file and output file
+    inFile.open("price.txt");
+
+    if (!inFile) {
+        cout << "Cannot open the input file."
+        << "The program terminates." << endl;
+        return 1;
+    }
+
+    outFile.open("price_output.out");
+    cout << "Processing data" << endl;
+
+    //Read file word by word
+    inFile >> burger_name >> burger_price;
+    inFile >> fries_name >> fries_price;
+    inFile >> icecream_name >> icecream_price;
+
+    //Output file
+    outFile << "The price of " << burger_name
+        << " is $" << burger_price <<"." << endl;
+
+    outFile << "The price of " << fries_name
+        << " is $" << fries_price << "." << endl;
+
+    outFile << "The price of " << icecream_name
+        << " is $" << icecream_price << "." << endl;
+    inFile.close(); // .close(): close a file
+    outFile.close();
+    cout << "Processing completed" << endl;
+
+    return 0;
+}

task1/_ref/Chapter03/price.txt

@@ -0,0 +1,3 @@
+burger 15
+fries 11
+ice-cream 9