### PrimePrime count sieve of Eratosthenes.

this problem is from codefights.

https://codefights.com/challenge/doXskkj8PMAJ27Epk/main

try to find prime numbers by using sieve of Eratosthenes.

and count luckyprimeprime.

I think this is not difficult though.

Recently Lucky learnt how to check if the given number is prime or not. Bunny, Lucky's friend, decided to give her a task to test her skills.

https://codefights.com/challenge/doXskkj8PMAJ27Epk/main

try to find prime numbers by using sieve of Eratosthenes.

and count luckyprimeprime.

I think this is not difficult though.

int c, t, s, i; int luckyandprimeprime(int l, int r) { int[] p = new int[100001]; s = p.length; for ( i = 2; i < s; i++, t=0) while ((t += i) < s) p[t]++; for (i = 0; i < l; i++) if (p[i] == 1) c++; for (i = l; i <= r; i++) { if (p[i] == 1) c++; if (p[c] == 1) t++; } return t; }

Recently Lucky learnt how to check if the given number is prime or not. Bunny, Lucky's friend, decided to give her a task to test her skills.

Let's call number

`P`

*Prime Prime*if the number of prime numbers in the range`[1, P]`

is prime. Bunny asked Lucky to calculate the number of *Prime Prime*numbers in the range`[l, r]`

. Can you you help her?**Example**

For

`l = 1`

and `r = 10`

, the output should be`luckyandprimeprime(l, r) = 4`

.
There're

`4`

prime numbers in the given range: `2`

, `3`

, `5`

and `7`

. Thus, *Prime Prime*numbers are`3`

, `4`

, `5`

and `6`

, `4`

numbers altogether.**Input/Output**

**[time limit] 3000ms (java)**

**[input] integer l***Constraints:*

`1 ≤ l ≤ r`

.**[input] integer r***Constraints:*

`l ≤ r ≤ 10`

.^{5}**[output] integer**The number of*Prime Prime*numbers in the range`[l, r]`

.

Recently Lucky learnt how to check if the given number is prime or not. Bunny, Lucky's friend, decided to give her a task to test her skills.

Let's call number

`P`

*Prime Prime*if the number of prime numbers in the range`[1, P]`

is prime. Bunny asked Lucky to calculate the number of *Prime Prime*numbers in the range`[l, r]`

. Can you you help her?**Example**

For

`l = 1`

and `r = 10`

, the output should be`luckyandprimeprime(l, r) = 4`

.
There're

`4`

prime numbers in the given range: `2`

, `3`

, `5`

and `7`

. Thus, *Prime Prime*numbers are`3`

, `4`

, `5`

and `6`

, `4`

numbers altogether.**Input/Output**

**[time limit] 3000ms (java)**

**[input] integer l***Constraints:*

`1 ≤ l ≤ r`

.**[input] integer r***Constraints:*

`l ≤ r ≤ 10`

.^{5}**[output] integer**The number of*Prime Prime*numbers in the range`[l, r]`

.

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