How to know the date of a calendar

It's easy to calculate the date of month easily.
Let us start now.
At first we need to take the calendar. So, it's here.

Here, we will calculate the date BUT the date must be selected in square form.
Example:
I have taken the date in square as 18,19,25,26.
Here we need is the sum of these numbers i.e. (18+19+25+26)=88.
So here we calculate
1. Divide the given result by 4.
   example: 88/4=22
2. Now subtract the above result with 4.
   example: 22-4=18
3. After the result is obtained, add the obtained result with 1,7 and 8.
    example: (18+1)=19
                    (18+7)=25
                    (18+8)=26
4. So, that's what we need.
Hence the result will be 18,19,25,26.

Now let us take another example to illustrate it.

Here, we take an example of 8,9,15,16.
First we need the sum of these numbers. here the sum is 48.
1. Divide it by 4. 48/4=12.
2. Then subtract by 4. 12-4=8.
3. Then add 1,7 and 8.
    i.e. 8+1=9
          8+7=15
          8+8=16.
So, that's it.
Enjoy it.