some changes in chapter06 examples

.vscode/settings.json

@@ -0,0 +1,7 @@
+{
+    "files.associations": {
+        "format": "cpp",
+        "span": "cpp",
+        "string_span": "cpp"
+    }
+}

CPlusPlus20ForProgrammers-master/examples/ch06/fig06_01.cpp

@@ -1,36 +1,49 @@
 // fig06_01.cpp
 // Initializing an array's elements to zeros and printing the array.
-#include <format> // C++20: This will be #include <format>
+//#include <../libraries/fmt/include/format.h> // C++20: This will be #include <format>
 #include <iostream>
 #include <array>
+#include <vector>
+#include <string>
 
-int main() {
-   std::array<int, 5> values{}; // values is an array of 5 int values
-
-   // initialize elements of array values to 0        
-   for (size_t i{0}; i < values.size(); ++i) {
-      values[i] = 0; // set element at location i to 0
-   }
-
-   std::cout << std::format("{:>7}{:>10}\n", "Element", "Value");
+template <typename T>
+void printArray(T& a, std::string tag){
+   std::cout << "Element       Value --->  "<<tag <<"\n" ;
 
    // output each array element's value
+   for (size_t i{0}; i < a.size(); ++i) {
+      std::cout <<  i << a[i]<<"\n";
+   }
+}
+int main() {
+   std::array<int, 5> values{}; // values is an array of 5 int values
+   std::array<double,10> floatarray;
+   std::vector<double> floatvector(20, 0);
+   for (size_t i{0}; i < floatarray.size(); i++)
+        floatarray[i] = i*i/10.0;
+        
+   // initialize elements of array values to 0        
    for (size_t i{0}; i < values.size(); ++i) {
-      std::cout << std::format("{:>7}{:>10}\n", i, values[i]);
+      values[i] = i*i; // set element at location i to 0
    }
 
-   std::cout << std::format("\n{:>7}{:>10}\n", "Element", "Value");
-
+   printArray(values,"values");
+   printArray(floatarray,"floatarray");
+   printArray(floatvector, "floatvector");
+   std::cout <<  "Element      Value\n" << "\n";
+    
+   floatvector.resize(5);
+   printArray(floatvector,"floatvector resized");
    // access elements via the at member function
    for (size_t i{0}; i < values.size(); ++i) {
-      std::cout << std::format("{:>7}{:>10}\n", i, values.at(i));
+      std::cout <<  i<<values.at(i) <<"\n";
    }
-
-   for (auto i : values){
-       std::cout << std::format("{:>7}{:>8}\n", i, values.at(i));
+/*   for (auto i : values){
+       std::cout <<  i << values.at(i)<<"\n";
    }
+   */
    // accessing an element outside the array's bounds with at
-   values.at(10); // throws an exception
+  // values.at(10); // throws an exception
 }
 
 /**************************************************************************