想要测试点10的数据，或大佬们帮我改改错

感谢，万分感谢！

#include<iostream>
#include<cstdio>
#include<cmath>
#include<queue>
#include<stack>
#include<vector>
#include<string>
#include<cstring>
#include<map>
#include<algorithm>
using namespace std;
long long n;
int k,len,num[10000005];
int main(){
	scanf("%lld %d",&n,&k);
	if(n==1&&k>1){
		printf("-1\n");
		return 0;
	}
	for(int i=1;i<=int(sqrt(n));i++){
		if(n%(long long)(i)==0){
			num[++len]=i;
			if(len==k){
				printf("%d\n",i);
				return 0;
			}
		}
	}
	int tmp=1;
	for(int i=len;i>=1;i--){
		if(n%(long long)(num[i])==(long long)(num[i])){
			tmp=0;
			continue;
		}
		if(len-i==k-len-tmp){
			printf("%lld\n",n/(long long)(num[i]));
			return 0;
		}
	}
	printf("-1\n");
	return 0;
}