diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/a.out b/CPlusPlus20ForProgrammers-master/examples/ch06/a.out
deleted file mode 100755
index f593ff9..0000000
Binary files a/CPlusPlus20ForProgrammers-master/examples/ch06/a.out and /dev/null differ
diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_02.cpp b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_02.cpp
index ad833fe..0c45af0 100644
--- a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_02.cpp
+++ b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_02.cpp
@@ -1,6 +1,6 @@
 // fig06_02.cpp
 // Initializing an array in a declaration.
-#include <format>
+//#include <format>
 #include <iostream>
 #include <array>
 
@@ -9,7 +9,7 @@ int main() {
 
    // output each array element's value
    for (size_t i{0}; i < values.size(); ++i) {
-      std::cout << std::format("{}  ", values.at(i));
+      std::cout <<  values.at(i) << "\n";
    }
 
    std::cout << "\n\n";
@@ -19,7 +19,7 @@ int main() {
 
    // output each array element's value
    for (size_t i{0}; i < values2.size(); ++i) {
-      std::cout << std::format("{}  ", values2.at(i));
+      std::cout <<  values2[i] << "\n";
    }
 
    std::cout << "\n";
diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_03.cpp b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_03.cpp
index 3c17f87..d5d4309 100644
--- a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_03.cpp
+++ b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_03.cpp
@@ -8,10 +8,14 @@ int main() {
 
    std::array items2{1, 2, 3, 4, 5};
    // display items before modification
+
+   for (int i{0}; i<items.size();i++)
+       std::cout <<  items[i] << "<-- items\n";
    std::cout << "items before modification: ";
    for (const int& item : items) { // item is a reference to a const int
       std::cout <<  item << "<-- items\n"; 
-   }                       
+   }     
+
    std::cout << "items2 before modification:\n";
    for (const int& item : items) { // item is a reference to a const int
       std::cout <<  item << "<-- items2\n";
@@ -38,8 +42,6 @@ int main() {
    for (const int& item : items2) {
       std::cout <<  item << "<-- items2\n";
    }
-
-
    // sum elements of items using range-based for with initialization
    std::cout << "\n\ncalculating a running total of items' values:\n";
    for (int runningTotal{0}; const int& item : items) {
diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_04.cpp b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_04.cpp
index 6653c4a..aad9c74 100644
--- a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_04.cpp
+++ b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_04.cpp
@@ -8,11 +8,15 @@ int main() {
    constexpr size_t arraySize{5}; // must initialize in declaration
 
    std::array<int, arraySize> values{}; // array values has 5 elements
-
+/*
    for (size_t i{0}; i < values.size(); ++i) { // set the values
       values.at(i) = 2 + 2 * i;
    }
-
+*/
+   for ( int index{0}; int& value : values) {
+      value = 2 + 2 * index;
+      index++;
+   }
    // output contents of array values in tabular format
    for (const int& value : values) {
       std::cout << value << "\n";
diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_06.cpp b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_06.cpp
index d9fb96f..94e6b07 100644
--- a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_06.cpp
+++ b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_06.cpp
@@ -1,6 +1,6 @@
 // fig06_06.cpp
 // Printing a student grade distribution as a primitive bar chart.
-#include <format>
+
 #include <iostream>
 #include <array>
 
diff --git a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_07.cpp b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_07.cpp
index 77540c1..941e3ae 100644
--- a/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_07.cpp
+++ b/CPlusPlus20ForProgrammers-master/examples/ch06/fig06_07.cpp
@@ -11,19 +11,25 @@ int main() {
    std::default_random_engine engine{rd()}; // rd() produces a seed 
    std::uniform_int_distribution randomDie{0, 6};
 
+   std::uniform_real_distribution<double> randomReal{0, 1};
+
    constexpr size_t arraySize{7}; // ignore element zero
    std::array<int, arraySize> frequency{}; // initialize to 0s
 
+
+   constexpr size_t N{7};
+   std::array<double, N> histogram{};
+
    // roll die 60,000,000 times; use die value as frequency index
    for (int roll{1}; roll <= 60'000'000; ++roll) {
-      ++frequency.at(randomDie(engine));
+       randomReal(engine);
    }
 
    std::cout <<  "Face " <<  " Frequency  \n";
 
    // output each array element's value
-   for (size_t face{1}; face < frequency.size(); ++face) {
-      std::cout << face << " " << frequency.at(face) << "\n";
+   for (size_t face{1}; face < histogram.size(); ++face) {
+      std::cout << face << " " << histogram.at(face) << "\n";
    }
 }