Explain nested switch case in C language

Problem

Write a C program to check the entered password by the user is valid or not based on his/her ID using nested switch case.

Solution

The solution is explained below −

• In C language, we can write inner switch which is placed in an outer switch.

• The case values of the inner and outer switch can have common values.

Rules

• An expression executes to a result.
• Constants and unique values must be used for case labels.
• Case labels has to be end with a colon ( : ).
• A break keyword has to be included in each case.
• There can be only one default label.
• We can write nested multiple switch statements.

Example

Following is the C program to check the entered password by the user is valid or not based on his/her ID using nested switch case −

#include <stdio.h>
int main(){
   int userid;
   int pwd;
   printf("enter userid:\n");
   scanf("%d",&userid);
   switch (userid){
      case 1234:
         printf("enter password:\n ");
         scanf("%d", & pwd);
      switch (pwd){
         case 0000:
            printf("Tutorials Point\n");
         break;
            default:
         printf("incorrect password");
            break;
      }
      break;
         default:
      printf("incorrect userid");
         break;
   }
}

Output

You will see the following output −

Run 1:enter userid:
1234
enter password:
0000
Tutorials Point
Run 2:
enter userid:
1234
enter password:
234
incorrect password