C program to find the size of given data type without using sizeof operator

Write a C program to find the size of given data type without using sizeof operator.

  #include <stdio.h>

  int main() {
        int size, ch;
        printf("Find the size of:\n");
        printf("1. Integer\t2. Character\n");
        printf("3. Float\t4. Double\n");
        printf("Enter your choice:");
        scanf("%d", &ch);

        switch(ch) {
                case 1:
                        /* adding 1 to integer pointer gives int size */
                        size = (int) (1 + (int *)0x0);
                        printf("Size of Integer: %d\n", size);
                        break;

                case 2:
                        /* adding 1 to char pointer gives size of char */
                        size = (int) (1 + (char *)0x0);
                        printf("Size of Character: %d\n", size);
                        break;

                case 3:
                        /* adding 1 to float ptr gives size of float */
                        size = (int) (1 + (float *)0x0);
                        printf("Size of Float: %d\n", size);
                        break;

                case 4:
                        /* adding 1 to double pointer gives size of double */
                        size = (int) (1 + (double *)0x0);
                        printf("Size of Double: %d\n", size);
                        break;

                default:
                        printf("Wrong Option!!\n");
                        break;
        }

        return 0;
  }

  Output:

  jp@jp-VirtualBox:~/$ ./a.out
  Find the size of:
  1. Integer 2. Character
  3. Float 4. Double
  Enter your choice:1
  Size of Integer: 4

  jp@jp-VirtualBox:~/$ ./a.out
  Find the size of:
  1. Integer 2. Character
  3. Float 4. Double
  Enter your choice:2
  Size of Character: 1

  jp@jp-VirtualBox:~/$ ./a.out
  Find the size of:
  1. Integer 2. Character
  3. Float 4. Double
  Enter your choice:3
  Size of Float: 4

  jp@jp-VirtualBox:~/$ ./a.out
  Find the size of:
  1. Integer 2. Character
  3. Float 4. Double
  Enter your choice:4
  Size of Double: 8