Program isn't clearly understand

#1

i didn’t understand the 20th line of code.

#2

@tushar1000xxxx,
In java we can make a 2D array with different number of arrays. So what we have done is that we have specified the number of rows in the 2D array, but we have different number of columns for each row.

Something like this is possible in java and this what we are trying to do:

int arr[][] = new int[3][];  
        arr[0] = new int[3];  
        arr[1] = new int[4];  
        arr[2] = new int[2];