MARBLES - Marbles

Hänschen dreams he is in a shop with an infinite amount of marbles. He is allowed to select n marbles. There are marbles of k different colors. From each color there are also infinitely many marbles. Hänschen wants to have at least one marble of each color, but still there are a lot of possibilities for his selection. In his effort to make a decision he wakes up. Now he asks you how many possibilites for his selection he would have had. Assume that marbles of equal color can't be distinguished, and the order of the marbles is irrelevant.


The first line of input contains a number T <= 100 that indicates the number of test cases to follow. Each test case consists of one line containing n and k, where n is the number of marbles Hänschen selects and k is the number of different colors of the marbles. You can assume that 1<=k<=n<=1000000.


For each test case print the number of possibilities that Hänschen would have had. You can assume that this number fits into a signed 64 bit integer.


10 10
30 7


hide comments
nonushikhar: 2015-10-24 12:00:14

silly mistakes got me 2wa !!!!!! otherwise very easy prob

dragonemperor: 2015-10-19 13:51:38

Bars and stars. AC at first go

farmers_rice: 2015-10-09 02:34:44

keep getting NZEC error even though the only exceptions thrown are in input/output

Sarthak Munshi: 2015-10-06 17:54:01


xproxmess: 2015-09-27 19:57:49

This is my code -
Why is it giving a wrong output for the second test case even though the logic is correct?

Yuvak Patel: 2015-07-28 16:38:07

GOT AC in 1 go, my 25th...

Akshay Aradhya: 2015-07-18 23:22:04

@dheeraj You logic is not correct.If long long int works then unsigned long long will definitely work. You must have used the wrong format specifier.

DHEERAJ KUMAR: 2015-06-09 23:55:53

using unsigned long long int costed me 2 WA's. instead use long long int to get AC :)

Usama: 2015-05-25 10:49:27

use unsigned long long give me many WAs

scyth3r: 2015-05-09 22:37:40

piece of cake....:D

Added by:Adrian Kuegel
Time limit:1s
Source limit:10000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL6 VB.NET
Resource:own problem