#include <bits/stdc++.h>
using namespace std;

#ifdef CKISEKI
#define safe cerr << __PRETTY_FUNCTION__ << " line " << __LINE__ << " safe\n"
#define orange(s...) orange_(#s, s)
#define debug(s...) debug_(#s, s)
template <typename ...T>
void debug_(const char *s, T ...a) {
    cerr << "\e[1;32m(" << s << ") = (";
    int cnt = sizeof...(T);
    (..., (cerr << a << (--cnt ? ", " : ")\e[0m\n")));
}
template <typename I>
void debug_(const char *s, I L, I R) {
    cerr << "\e[1;32m[ " << s << " ] = [ ";
    for (int f = 0; L != R; ++L)
        cerr << (f++ ? ", " : "") << *L;
    cerr << " ]\e[0m\n";
}
#else
#define safe ((void)0)
#define orange(...) safe
#define debug(...) safe
#endif

int main() {
    cin.tie(nullptr)->sync_with_stdio(false);
    int n, k;
    cin >> n >> k;

    vector<int> a(n);
    vector<vector<int>> buc(k);
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        --a[i];
        buc[a[i]].push_back(i);
    }

    const int inf = 1e9;
    int ans = inf;

    multiset<int> ms;

    vector<int> last(k, -1);

    for (int i = 0, j = 0; i < n; i++) {
        if (i == buc[a[i]].back()) {
            // j >= buc[a[i]].front()
            while (j <= buc[a[i]].front()) {
                ++j;
            }
        }

        if (last[a[i]] != -1) {
            ms.erase(ms.find(last[a[i]]));
        }
        ms.insert(i);
        last[a[i]] = i;
        if (ms.size() == k && j <= *ms.begin()) {
            ans = min(ans, i - j + 1);
        }
    }


    if (ans == inf)
        cout << 0 << '\n';
    else
        cout << ans << '\n';

    return 0;
}