#include <iostream>
#include<vector>
#include<unordered_map>
using namespace std;

int main() {
	// your code goes here
	vector<int> a={1,3,5,6,1,9,8};
	unordered_map<int,int> m;
	int k=4;
	int dist=-1;
	for(int i=0;i<a.size();i++) {
		int curr=a[i];
		for(int j=i+1;j<a.size();j++) {
			if(a[j]==curr) {
				dist=j-i;
				if(dist<=k) {
				cout<<dist<<endl;
				}
			}
		}
	}
	return 0;
}