Nested switch statement in C++

Switch-case statements:

These are a substitute for long if statements that compare a variable to several integral values

The switch statement is a multiway branch statement. It provides an easy way to dispatch execution to different parts of code based on the value of the expression.
Switch is a control statement that allows a value to change control of execution.

Syntax:

switch (n)
{
    case 1: // code to be executed if n = 1;
  break;
    case 2: // code to be executed if n = 2;
  break;
    default: // code to be executed if 
      // n doesn't match any cases
}

Nested-Switch Statement:

Nested-Switch statements refers to Switch statements inside of another Switch Statements.

Syntax:

switch(n)
{
  // code to be executed if n = 1;
  case 1: 
    
  // Nested switch
  switch(num) 
  {
    // code to be executed if num = 10
    case 10: 
      statement 1;
      break;
      
    // code to be executed if num = 20
    case 20: 
      statement 2;
      break;
      
    // code to be executed if num = 30
    case 30: 
      statement 3;
      break;
      
      // code to be executed if n 
      // doesn't match any cases
      default: 
  }
  
  
  break;
    
  // code to be executed if n = 2;
  case 2:
    statement 2;
    break;
  
  // code to be executed if n = 3;
  case 3: 
    statement 3;
    break;
  
   // code to be executed if n doesn't match any cases
   default: 
}

Example:

// Following is a simple program to demonstrate 
// syntax of Nested Switch Statements. 
  
#include <iostream> 
using namespace std; 
  
int main() 
{ 
    int x = 1, y = 2; 
  
    // Outer Switch 
    switch (x) { 
  
    // If x == 1 
    case 1: 
  
        // Nested Switch 
  
        switch (y) { 
  
        // If y == 2 
        case 2: 
            cout << "Choice is 2"; 
            break; 
  
        // If y == 3 
        case 3: 
            cout << "Choice is 3"; 
            break; 
        } 
        break; 
  
    // If x == 4 
    case 4: 
        cout << "Choice is 4"; 
        break; 
  
    // If x == 5 
    case 5: 
        cout << "Choice is 5"; 
        break; 
  
    default: 
        cout << "Choice is other than 1, 2 3, 4, or 5"; 
        break; 
    } 
    return 0; 
} 

Output:

Choice is 2

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