Problems
Primes
Primes
Let $m$ and $n~(2 \le m < n \le 10^7)$ be two integers. Consider the following set:
$Prime~(m, n)$ = \{ $p$ | $p$ prime and $m \le p \le n$ \}.
Find the cardinality of the set $Prime~(m, n)$.
\InputFile
Consists of several tests. The input of each test is represented on a single line. Any two consecutive tests are separated by an empty line. For each test, the values for $m$ and $n$ are given on the same line, separated by exactly one space.
\OutputFile
For each test, the result will be written on a different line (the tests will have the same order as in the input). The results of any two consecutive tests will be separated by an empty line. For each test, the result will be the cardinal of the set $Prime~(m, n)$.
Input example #1
4 12 70 110 5 150
Output example #1
3 10 33