Submit | All submissions | Best solutions | Back to list |
ETFD - Euler Totient Function Depth |
Lucky is fond of Number theory, one day he was solving a problem related to Euler Totient Function (phi) and found an interesting property of phi : phi(1) = 1, and for x > 1: phi(x) < x.
So if we define a sequence with a0 = x, and for n > 0: an = phi(an-1), this sequence will be constant equal to 1 starting from some point. Lets define depth(x) as minimal n such that an = 1.Now he is wondering how many numbers in a given range have depth equal to given number k. As you are a good programmer help Lucky with his task.
Input
Your input will consist of a single integer T followed by a newline and T test cases.
Each test cases consists of a single line containing integers m, n, and k.
Output
Output for each test case one line containing the count of all numbers whose depth equals to k in given range [m, n].
Constraints
T < 10001
1 ≤ m ≤ n ≤ 106
0 ≤ k < 20
Example
Input: 5 1 3 1 1 10 2 1 10 3 1 100 3 1 1000000 17 Output: 1 3 5 8 287876
Explanation: suppose number is 5 ; its depth will be 3. ( 5 → 4 → 2 → 1 )
Note: Depth for 1 is 0.
Added by: | [Lakshman] |
Date: | 2015-01-14 |
Time limit: | 2s |
Source limit: | 50000B |
Memory limit: | 1536MB |
Cluster: | Cube (Intel G860) |
Languages: | All except: ASM64 JS-MONKEY |
Resource: | ETF |
hide comments
|
|||||||
2021-07-08 14:51:55
I pre-computed in 2D array. But my running time was 1.41 s :( , other people have less than 0.2 s. I think there is a better way. |
|||||||
2020-07-18 17:32:24
AC in 1 go :-D |
|||||||
2020-06-26 10:30:45
@lakshman can u pls look at my code i am getting tle |
|||||||
2018-05-24 23:08:11
@Lakshman can you please tell where I need to optimize my code? I am getting TLE ==(Lakshman)==>Your query part is taking time and in the worst case it is O(n). Last edit: 2018-06-08 08:33:44 |
|||||||
2018-03-22 03:15:31
just precalculate ...... and ............. AC(0.08 sec) Last edit: 2018-03-22 03:16:08 |
|||||||
2017-10-12 09:34:55
huh..finally AC in 0.18sec after 4 WA.....!!! Last edit: 2017-10-12 09:35:54 |
|||||||
2017-08-18 09:25:48
Too many times TLE but after get the AC......precomputation is the best |
|||||||
2017-08-15 21:48:26
@Lakshman please check my approach.....it is giving TLE ==Lakshman==> In worst for each query it is taking $O(n)$. Here you need $O(log n) $for each query. Last edit: 2018-01-26 14:03:35 |
|||||||
2017-07-03 12:11:55
finally AC after so many WA!!!!! |
|||||||
2016-12-11 08:41:32
precomputation at its best :) |