C++ Nested If
Nested If
You can also place an if statement inside another if. 
This is called a nested if statement.
A nested if lets you check for a condition only if another condition is already true.
Syntax
if (condition1) {
  // code to run if condition1 is true
  if (condition2) {
    // code to run if both condition1 and condition2 are true
  }
}
Example
In this example, we first check if x is greater than 10.  
If it is, we then check if y is greater than 20:
Example
int x = 15;
int y = 25;
if (x > 10) {
  cout << "x is greater than 10\n";
  // Nested if
  if (y > 20) {
    cout << "y is also greater than 20\n";
  }
}
Result:
x is greater than 10
y is also greater than 20
Real-Life Example
Nested if statements are useful when you need to test multiple conditions that depend on each other.  
For example, checking if a person is old enough to vote, and if they are a citizen:
Example
int age = 20;
bool isCitizen = true;
if (age >= 18) {
  cout << "Old enough to vote.\n";
  if (isCitizen) {
    cout << "And you are a citizen, so you can vote!\n";
  } else {
    cout << "But you must be a citizen to vote.\n";
  }
} else {
  cout << "Not old enough to vote.\n";
}
Result:
Old enough to vote.
And you are a citizen, so you can vote!
Notes
- You can nest as many ifstatements as you want, but avoid making the code too deep - it can become hard to read.
- Nested ifis often used together withelseandelse iffor more complex decision making.
 
