CLOPPAIR - Closest Point Pair

You are given N points on a plane and your task is to find a pair of points with the smallest Euclidean distance between them.

All points will be unique and there is only one pair with the smallest distance.


First line of input will contain N (2<=N<=50000) and then N lines follow each line contains two integers giving the X and Y coordinate of the point. Absolute value of X,Y will be at most 10^6.


Output 3 numbers a b c, where a, b (a<b) are the indexes (0 based) of the point pair in the input and c is the distance between them. Round c to 6 decimal digits.

See samples for more clarification.

0 0
0 1
100 45
2 3
9 9


0 1 1.000000
0 0
-4 1
-7 -2
4 5
1 1


0 4 1.414214

hide comments
atomic_lattice: 2023-05-22 10:01:12

REMEMBER a < b and EXACTLY 6 digits

mreza5760: 2022-10-28 11:31:26

3 important thing
1. find the answer in long long then get the sqrt
2. be careful about a < b
3. use 1ll* in some part of code

ppap_1264589: 2021-09-12 17:33:47

Make sure your output is (a < b)
Make sure that you use cout << fixed << setprecision(6) before printing answer
Finally, make sure your algorithm is correct then you would get accepted

princemishra: 2021-06-05 14:53:36

even n(logn)^2 worked

shashwat28: 2021-01-02 13:23:43

Those who are stuck on TC 12 ,it wants exactly 6 digits after decimal no more no less :)

cis_pie: 2020-08-18 17:37:05

Can be done using line sweep algorithm in nlogn

manish1101: 2020-06-13 11:02:06

I have submitted more than 15 times but still stuck at line 179 in my code <snip>
Please someone help

Last edit: 2022-07-26 21:52:08
Saksham : 2020-04-03 21:30:21

'rounding to 6 digits' - this got me.

Eddy Cael: 2020-01-16 05:09:30

You can use long long or double, it no makes a real difference.

Eddy Cael: 2020-01-16 05:04:33

Don't waste time in precision issues... Make sure that the algorithm is right and a<b. That's all.

Added by:SALVO
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ASM64
Resource:Standard Problem