Problem:
Score : 200 points

Problem Statement

You are given positive integers A and B.

Find the K-th largest positive integer that divides both A and B.

The input guarantees that there exists such a number.

Constraints

All values in input are integers.

1 \leq A, B \leq 100

The K-th largest positive integer that divides both A and B exists.

K \geq 1

Input

Input is given from Standard Input in the following format:

A B K

Output

Print the K-th largest positive integer that divides both A and B.

Sample Input 1

8 12 2

Sample Output 1

2

Three positive integers divides both 8 and 12: 1, 2 and 4.
Among them, the second largest is 2.

Sample Input 2

100 50 4

Sample Output 2

5

Sample Input 3

1 1 1

Sample Output 3

1

Solution in C (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<stdlib.h>
int main(){
  int a,b,k;
  int i;
  scanf("%d %d %d",&a,&b,&k);
  int *sosuu;
  sosuu=malloc(k*sizeof(int));
  int max;
  if(a>b)
    max=a;
  else
    max=b;
  int count=0;
  for(i=2;i<max;i++){
    if(a%i==0&&b%i==0)
      sosuu[count++]=i;
    if(count==k)
      break;
  }
  printf("%d",sosuu[count-1]);
    	
  return 0;
}