#include <iostream>
#include <vector>
#include <set>
#include <limits.h>

using namespace std;

int main()
{
    int n, c, i, out = INT_MAX;
    cin >> n >> c;

    vector<int> lights(n);
    for (i = 0; i < n; i++) {
        cin >> lights[i];
    }

    vector<int> colors(c, 0);
    set<int> present;

    int back = 0;
    i = 0;
    while (i < n) {
        if (present.size() < c) {
            present.insert(lights[i]);
            colors[lights[i]]++;
            i++;
        }
        if (present.size() == c) {
            if (out > i - back) {
                out = i - back;
            }
            colors[lights[back]]--;
            if (colors[lights[back]] == 0) {
                present.erase(lights[back]);
            }
            back++;
        }
    }
    cout << out;
}