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
roy_24:
20160624 16:44:33
Dont complicate, can be done without using stl or memoization. Think easy. 

baadshah_:
20160623 13:50:44
use set STL


noob909:
20160616 07:08:29
memoization :D ac in 1 go! 

vineetpratik:
20160613 19:13:09
Ac in one go , :D m happy. 

sonali9696:
20160607 18:52:14
Concentrate on all possible single digits, you will know which two are important. Happy coding :) 

nonushikhar:
20160323 20:59:27
do math for n=10 or 15 and u'll get it 

akshayvenkat:
20160211 15:05:52
please don't complicate it much. its actually a very simple problem. i ll give you a tip. the count variable has a certain limiting value. Beyond that, the answer will always be 1. With this, you should be able to proceed.. And write the code for 1 INPUT alone. "number of input files is 32 " doesn't concern the problem in any way.. Good luck (y) Last edit: 20160211 15:06:11 

aditya1997:
20160209 00:14:30
set.....the key to AC :) 

Aqib Ahmed J:
20160131 07:48:11
Tick mark in one go :) 

Parikshith Rai:
20160123 07:39:30
got 3 nzecs only because i thought that there are 32 test cases.

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 