#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
using namespace std;

int main() {
    int n, m;
    cin >> n >> m;
    vector<int> a(n);
    for (int i = 0; i < n; ++i) cin >> a[i];
    for (int i = 0; i < m; ++i) {
        int t, l, r;
        cin >> t >> l >> r;
        if (t == 1) {
            int x, y;
            cin >> x >> y;
            auto b = a.begin() + l;
            auto c = a.begin() + r + 1;
            replace(b, c, x, y);
        } else {
            int k;
            cin >> k;
            set<int> b(a.begin(), a.end());
            int s = 0, found = 0;
            for (int c : b) {
                if (k + s < c) {
                    cout << k + s << endl;
                    found = 1;
                    break;
                }
                s++;
            }
            if (!found) cout << k + s << endl;
        }
    }
    return 0;
}