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

struct RU {
	using type1 = int;
	using type2 = int;
	static type1 id1() { return INT_MAX; }
	static type2 id2() { return -1; }
	static type1 op1(const type1& l, const type1& r) { return min(l, r); }
	static type1 op2(const type1& l, const type2& r) { return r == -1 ? l : r; }
	static type2 op3(const type2& l, const type2& r) { return r == -1 ? l : r; }
};

template <typename M>
class LazySegmentTree {
	using T1 = typename M::type1;
	using T2 = typename M::type2;
	const int n;
	vector<T1> data;
	vector<T2> lazy;
	int size(int n) {
		int res = 1;
		while (res < n) res <<= 1;
		return res;
	}
	void push(int node) {
		if (lazy[node] == M::id2()) return;
		if (node < n) {
			lazy[node * 2] = M::op3(lazy[node * 2], lazy[node]);
			lazy[node * 2 + 1] = M::op3(lazy[node * 2 + 1], lazy[node]);
		}
		data[node] = M::op2(data[node], lazy[node]);
		lazy[node] = M::id2();
	}
	void suc(int l, int r, int node, int lb, int ub, T2 val) {
		if (ub <= l || r <= lb) return;
		if (l <= lb && ub <= r) {
			lazy[node] = M::op3(lazy[node], val);
			return;
		}
		push(node);
		int c = (lb + ub) / 2;
		suc(l, r, node * 2, lb, c, val);
		suc(l, r, node * 2 + 1, c, ub, val);
		data[node] = M::op1(M::op2(data[node * 2], lazy[node * 2]), M::op2(data[node * 2 + 1], lazy[node * 2 + 1]));
	}
	T1 sub(int l, int r, int node, int lb, int ub) {
		if (ub <= l || r <= lb) return M::id1();
		if (l <= lb && ub <= r) return M::op2(data[node], lazy[node]);
		push(node);
		int c = (lb + ub) / 2;
		return M::op1(sub(l, r, node * 2, lb, c), sub(l, r, node * 2 + 1, c, ub));
	}
public:
	LazySegmentTree(int n_) : n(size(n_)), data(n * 2, M::id1()), lazy(n * 2, M::id2()) {}
	void update(int l, int r, T2 val) {
		suc(l, r + 1, 1, 0, n, val);
	}
	T1 find(int l, int r) {
		return sub(l, r + 1, 1, 0, n);
	}
};

int main()
{
	ios::sync_with_stdio(false), cin.tie(0);
	int n, q, type, s, t, x;
	cin >> n >> q;
	LazySegmentTree<RU> lst(n);
	while (q--) {
		cin >> type;
		if (type) {
			cin >> x;
			printf("%d\n", lst.find(x, x));
		}
		else {
			cin >> s >> t >> x;
			lst.update(s, t, x);
		}
	}
	return 0;
}