PROGRAMMING:Find the number of numbers that can be divided by 3 or 5 or 7 in the specified interval

Input 2 positive integers a and B (a < = B and not beyond the range of 32-bit signed integers) from the keyboard, and output the number of integers that can be divided by 3 or 5 or 7 that is greater than or equal to a and less than or equal to B.
###Input format:
2 lines, 1 integer per line!
###Output format:
1 row, the number of numbers that can be divided by 3 or 5 or 7, which is greater than or equal to a and less than or equal to B.
###Input example:
Here is a set of inputs. For example:
```in
one
ten
```
###Output example:
The corresponding output is given here. For example:
```out
six
```







answer：If there is no answer, please comment