more exercises, one unfinished

8 files changed, 171 insertions, 0 deletions

diff --git a/4p13.cpp b/4p13.cpp
new file mode 100644
index 0000000..b5cfdf1
--- /dev/null
+++ b/4p13.cpp
@@ -0,0 +1,23 @@
+#include <iostream>
+
+/*
+ *
+ * 4.13
+ *
+ * 
+ */
+
+int main () {
+	
+	
+	int i1;
+	int i2;
+	double d1;
+	double d2;
+	double threepointfive = 3.5; // made a variable for 3.5 to avoid compiler errors
+	d1 = i1 = threepointfive; // i == 3, d == 3
+	i2 = d2 = threepointfive; // d == 3.5, i == 3
+	std::cout << d1 << " <-d1(3) (3)i1-> " << i1 << std::endl;
+	std::cout << d2 << " <-d2(3.5) (3)i2-> " << i2 << std::endl;
+	return 0;
+}
diff --git a/4p14.cpp b/4p14.cpp
new file mode 100644
index 0000000..84fe963
--- /dev/null
+++ b/4p14.cpp
@@ -0,0 +1,21 @@
+#include <iostream>
+
+/*
+ *
+ * 4.14
+ *
+ *
+ */
+
+int main () {
+
+	int i = 0;
+
+	//if(42 = i) {} Not valid, error
+	int ifs2 = i = 42;
+	if(ifs2) { // evaluates as true because nonZero == true
+		std::cout << "..." << std::endl;
+	}
+	
+	return 0;
+}
diff --git a/4p15.cpp b/4p15.cpp
new file mode 100644
index 0000000..7ac66d5
--- /dev/null
+++ b/4p15.cpp
@@ -0,0 +1,26 @@
+#include <iostream>
+
+/*
+ *
+ * 4.15
+ *
+ *
+ */
+
+int main () {
+
+	double dval;
+	int ival;
+	int *pi;
+	/*
+	ival = 0;
+	dval = 0;
+	pi = 0;
+
+	I don't really see a reason not to do it this way but both of these examples work
+	*/
+	ival = dval = 0;
+	pi = 0;
+	std::cout << dval << ival << pi << std::endl;
+	return 0;
+}
diff --git a/4p16.cpp b/4p16.cpp
new file mode 100644
index 0000000..5205446
--- /dev/null
+++ b/4p16.cpp
@@ -0,0 +1,29 @@
+#include <iostream>
+
+/*
+ *
+ * 4.16
+ *
+ * Added a mockup getPtr function to demonstrate
+ */
+
+int *getPtr(int *f) {
+	
+	return f;
+}
+
+int main () {
+	
+	int f;
+	int *p = nullptr;
+	if ((p = getPtr(&f)) != 0) {
+		std::cout << "not nullptr" << std::endl;
+	}
+
+	int i = 1024;
+	if (i == 1024) {
+		std::cout << "i: 1024" << std::endl;
+	}
+	
+	return 0;
+}
diff --git a/4p17.cpp b/4p17.cpp
new file mode 100644
index 0000000..63459d8
--- /dev/null
+++ b/4p17.cpp
@@ -0,0 +1,14 @@
+
+/*
+ *
+ * 4.17
+ *
+ *
+ */
+
+int main () {
+
+	// Prefix increments will increment the object by 1 and return the incremented object as result.
+	// Postfix increment will increment the object by 1 but return a copy of the object before being incremented.
+	return 0;
+}
diff --git a/4p18.cpp b/4p18.cpp
new file mode 100644
index 0000000..0788e51
--- /dev/null
+++ b/4p18.cpp
@@ -0,0 +1,20 @@
+
+/*
+ *
+ * 4.18
+ *
+ *
+ */
+
+int main () {
+	/*
+	auto pbeg = v.begin();
+	while (pbeg != v.end() && *beg >= 0)
+		cout << *pbeg++ << endl;
+	*/
+
+	// It would increment pbeg by 1 and then dereference and print.
+	// This would mean that the first element in the vector is not printed
+	// This would also mean dereferencing whatever is at v.end() which is not a good idea.
+	return 0;
+}
diff --git a/4p19.cpp b/4p19.cpp
new file mode 100644
index 0000000..ab94f28
--- /dev/null
+++ b/4p19.cpp
@@ -0,0 +1,19 @@
+#include <iostream>
+#include <vector>
+
+/*
+ *
+ * 4.19
+ *
+ *
+ */
+
+int main () {
+
+	int *ptr = nullptr;
+	int aa = 12374;
+	int ival = 0;
+	ptr = &aa;
+	vector<int> vec;
+	return 0;
+}
diff --git a/increment-tests.cpp b/increment-tests.cpp
new file mode 100644
index 0000000..d5b5665
--- /dev/null
+++ b/increment-tests.cpp
@@ -0,0 +1,19 @@
+#include <iostream>
+
+/*
+ *
+ * 
+ *
+ *
+ */
+
+int main () {
+
+	int i = 0;
+	int j = 0;
+	int k = 0;
+	j = ++i;
+	k = i++;
+	std::cout << i << " " << j << " " << k << std::endl;
+	return 0;
+}