HPYNOS  Happy Numbers I
The process of “breaking” an integer is defined as summing the squares of its digits. For example, the result of breaking the integer 125 is (1^{2} + 2^{2} + 5^{2}) = 30. An integer N is happy if after “breaking” it repeatedly the result reaches 1. If the result never reaches 1 no matter how many times the “breaking” is repeated, then N is not a happy number.
TASK
Write a program that given an integer N, determines whether it is a happy number or not.
CONSTRAINTS
2 ≤ N ≤ 2,147,483,647
Input
A single line containing a single integer N.
Output
A single line containing a single integer T which is the number of times the process had to be done to determine that N is happy, or 1 if N is not happy.
Example
Input: 19 Output: 4
1) 19 : 1^{2} + 9^{2} = 82 2) 82 : 82 + 2^{2} = 68 3) 68 : 6^{2} + 8^{2} = 100 4) 100 : 1^{2 }+ 0^{2} + 0^{2} = 1
The solution is 4 because we discovered that the integer 19 is happy after we repeated the process 4 times.
Input: 204 Output: 1
204 –> 20 –> 4 –> 16 –> 37 –> 58 –> 89 –> 145 –> 42 –> 20 –> 4 –> 16 –> 37 –> 58 –> 89 –> 145 ……
204 is not a happy number because after breaking it several times the results start repeating so we can deduce that if we continue breaking it, the result will never reach 1.
Number of input files is 32.
Don't use precalculated values (Don't Cheat)!!!
hide comments
loser_404:
20210611 17:05:23
Lol, constrains almost give me heart attack. But simple brute force works fine 

tejasreddyk:
20210202 17:01:41
wow ac in one go, maintained a vector to store past 8 values, ifg they repeat then its not happy number


madhuri_911:
20201224 07:47:52
very easy...


abhineelnandi:
20200905 09:04:15
Ac at one go 

neel_butani:
20200625 07:44:31
try different test case from 1 to 10 , you will notice a pattern and that's it !!ac 

navdeep1469:
20200618 13:52:46
Do not complicate things. Solution is hidden in the test case itself. 

dante_part_2:
20200424 16:09:49
How can we precalculate values?? 

abhishek_251:
20200419 20:55:57
i hate brute force kinda questions 

raviteja_30:
20190911 18:51:28
50th one.......! wow , feeling happy. 

xxxadityaxxx:
20190902 19:57:27
used HashSet 
Added by:  Rofael Emil 
Date:  20101103 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  Egyptian Olympiad in Informatics ( EOI ) 2009, August 14  21, Cairo 