IITKWPCH  Find Number Of Pair of Friends
You are given n numbers. Any two number are called friends if they have some digit common. eg. (11, 12) and (15, 4561) are friends but (33, 556) is not.
Find out no of pairs which are friends.
(Formally speaking Let us assume the n numbers be are stored in array a[]. You have to find out number of i and j pairs such that i < j and a[i] and a[j] are friends.).
Input
T : no of test cases (T >= 1 && T <= 7)
For each test case, you will be given two lines, first line will contain n <= 10^6
then in next n line each line will contain a single integer representing a[i] (a[i] >= 1 && a[i] <= 10^18)
Output
For every test case print a line
containing number of such pairs as mentioned in the problem statement.
Example
Input: 4
2
12 13
3
10 12 24
3
5 6 7
4
10 11 211 3
Output:
1
2
0
3
hide comments
nadstratosfer:
20190329 06:23:05
Downvoted for TL preventing submissions in slower languages, albeit from the comments I infer it's the fault of the SPOJ code recalculating limits after compiler update rather than psetters. With dataset containing a million numbers per case, O(n^2) would obviously fail at far more relaxed limit.


chetan4060:
20180109 20:55:50
nice problem with best concept; 

geoffreymace7:
20180101 22:57:31
Same as http://www.spoj.com/problems/KOMPICI/


Shubham:
20150701 13:12:45
nyc problem.... learnt a lot :) 

kartikay singh:
20150604 07:31:49
learned something new :)


ANUJ RATHORE:
20150601 12:09:02
will O(n2) pass?


ggkjh:
20140805 19:09:37
considering a[i] as a string of size 25 got AC...in 0.53 sec..where as considering a[i] as a long long data type got AC in 1.78 sec...Can anyone justify the reason for this weird behavior...????


Sir_Ostara:
20140116 16:16:15
TLE..taking input as string and using printf and scanf. help??


Luka:
20131231 11:00:06
KOMPICI 

Piyush Kapoor:
20131226 14:05:12
I remember this question was a part of Directi coding contest for hiring at MNNIT Allahabad. 
Added by:  praveen123 
Date:  20130805 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  general problem 