Added Day 7 Content - ternary operator (#110)

docs/day-07/ternary-operator.md

@@ -6,15 +6,101 @@ sidebar_label: "Ternary Operator"
 slug: ternary-operator-in-cpp
 ---
 
-TASK:
 
-1. What is the Ternary Operator in C++?
-2. Explain the Syntax of Ternary Operator in C++.
-3. How does the Ternary Operator work in C++?
-4. C++ Ternary Operator Example
-5. C++ Ternary Operator with Nested Ternary Operator
+## What is the Ternary Operator in C++?
+In C++, the ternary operator, also known as **conditional operator**,  is a shorthand way of writing conditional (if-else) statements. It is known as ternary operator because it takes **three** operands. This operator can be used to replace simple multi-line if-else statements with a single line of code.
+
 
 
-IMAGE FILE:
 ![Ternary in CPP](../../static/img/day-07/ternary-operator.png)
 
+## Syntax of Ternary Operator in C++
+The ternary/conditional operator `(? :)` takes 3 operands (`condition`, `expression_1` and `expression_2`). The basic syntax of ternary operator is:
+```cpp
+condition ? expression_1 : expression_2;
+```
+The above statement, if written using `if-else`, is the same as:
+```cpp
+if(condition){
+    expression_1;
+}
+else{
+    expression_2;
+}
+```
+
+## How does the Ternary Operator work in C++?
+The ternary operator works by first evaluating the condition. If the condition evaluates to `true`, then the code corresponding to `expression_1` is executed. If the condition evaluates to `false`, then code corresponding to `expression_2` is executed.
+
+## C++ Ternary Operator Examples
+### 1. Print the max of two integers 
+The following program takes two integers as input and prints maximum of them.
+
+```cpp
+#include<iostream>
+using namespace std;
+
+int main(){
+    int a, b;
+    cout<<"Enter two numbers: ";
+    cin>>a>>b;
+    int maxi = (a > b) ? a : b;
+    cout<<"Max number is "<<maxi<<endl;
+    return(0);
+}
+```
+If condition `a>b` evaluates to `true`, then `maxi` stores the larger value `a`. If condition `a>b` evaluates to `false`, then `maxi` stores the value of `b`.
+
+### 2. Get absolute value of an integer 
+The function `get_abs` takes an integer as input and returns the absolute value of integer. The function shows the use of `return` with ternary operator.
+
+```cpp
+#include <iostream>
+using namespace std;
+
+int get_abs(int n){
+    return (n>=0 ? n : -n);
+}
+
+int main()
+{
+    int n;
+    cout << "Enter a number: ";
+    cin >> n;
+    cout << "Absolute value is " << get_abs(n) << endl;
+    return (0);
+}
+```
+
+``
+NOTE:
+``
+The following syntax for the function is **incorrect**:
+```cpp
+int get_abs(int n){
+    n>=0 ? return(n) : return(-n);
+}
+// This is because return is a statement 
+// whereas ternary operator requires operands 
+// to be expression and not statement.
+```
+
+## C++ Ternary Operator with Nested Ternary Operator
+The following program takes three integers as input and prints maximum of them.
+```cpp
+#include<iostream>
+using namespace std;
+
+int main(){
+    int a, b, c;
+    cout<<"Enter three numbers: ";
+    cin>>a>>b>>c;
+    int maxi = (a > b) ? ((a > c) ? a : c) : ((b>c) ? b : c);
+    cout<<"Max number is "<<maxi<<endl;
+    return(0);
+}
+```
+
+If condition `a>b` evaluates to `true`, then we check the condition `a>c`. If `a>c` evaluates to `true`, then `maxi` stores the value of `a`, else `maxi` stores the value of `c`.
+
+ If condition `a>b` evaluates to `false`, then we check the condition `b>c`. If `b>c` evaluates to `true`, then `maxi` stores the value of `b`, else `maxi` stores the value of `c`.