#include <bits/stdc++.h>
using namespace std;
int N = 3000001; 
int M = 1000001;
int main() {
	vector<vector<int>>v ; 
	v.resize(N) ; 
	int n; 
	scanf("%d" , &n) ; 
	
	for (int i =0 ; i<n ; ++i) {
		int x ; 
		cin>>x;
		x+=M ; 
		v[x].push_back(i) ; 
	}
	int mx = 1;
	for(int i =0 ; i<N ; ++i) {
		if (v[i].size()){
			
//		cout<< v[i][0]<<" "<<v[i][v[i].size()-1]<<endl;
		mx = max(mx , v[i][v[i].size()-1]-v[i][0]+1) ; 
			
		}

	}
	cout<<mx<<endl;
	return 0;
	
}