#pragma GCC optimize("Ofast","unroll-loops")
#pragma comment(linker, "/stack:200000000")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#include<bits/stdc++.h>
using namespace::std;
//struct __INIT{__INIT(){cin.tie(0);ios::sync_with_stdio(false);cout<<fixed<<setprecision(15);}} __init;
__attribute__((constructor))
void init(){
	cin.tie(0);
	ios::sync_with_stdio(false);
	cout<<fixed<<setprecision(15);
}
// random_device rd;
// mt19937 mt(rd());
// #include <boost/numeric/interval.hpp>
// #include <boost/numeric/interval/io.hpp>
// #include <boost/intrusive/rbtree.hpp>
// #include <boost/dynamic_bitset.hpp>
// #include <boost/geometry.hpp>
// #include <boost/geometry/geometries/linestring.hpp>
// #include <boost/geometry/geometries/polygon.hpp>
// #include <boost/geometry/geometries/point_xy.hpp>
// #include <boost/math/tools/minima.hpp>
// using boost::math::tools::brent_find_minima;
// #include <boost/multiprecision/cpp_dec_float.hpp>
// #include <boost/multiprecision/cpp_int.hpp>
// namespace mp = boost::multiprecision;
// typedef mp::number<mp::cpp_dec_float<0>> cdouble;
// typedef mp::cpp_int cint;
// #include <boost/unordered_map.hpp>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/priority_queue.hpp>
#include<ext/pb_ds/tag_and_trait.hpp>
template<typename T=long long>using pbds=__gnu_pbds::tree<T,__gnu_pbds::null_type,less<T>,__gnu_pbds::rb_tree_tag,__gnu_pbds::tree_order_statistics_node_update>;
template<typename T=long long>using pbds_map=__gnu_pbds::tree<T,T,less<T>,__gnu_pbds::rb_tree_tag,__gnu_pbds::tree_order_statistics_node_update>;
template<typename T=long long>using pqueue =__gnu_pbds::priority_queue<T, less<T>,__gnu_pbds::rc_binomial_heap_tag>;
typedef long long lint;
typedef long long ll;
typedef long double ldouble;
typedef vector<lint> vec;
typedef vector<vector<lint>> mat;
typedef vector<vector<vector<lint>>> mat3;
typedef vector<double> dvec;
typedef vector<vector<double>> dmat;
typedef vector<vector<vector<double>>> dmat3;
typedef vector<string> svec;
typedef vector<vector<string>> smat;
typedef vector<vector<vector<string>>> smat3;
template<typename T>using Vec=vector<T>;
template<typename T>using Mat=vector<vector<T>>;
template<typename T>using Mat3=vector<vector<vector<T>>>;
template<typename T>using Mat4=vector<vector<vector<vector<T>>>>;
template<typename S,typename T>using pvec=vector<pair<S,T>>;
template<typename S,typename T>using pmat=vector<vector<pair<S,T>>>;
template<typename S,typename T>using pmat3=vector<vector<vector<pair<S,T>>>>;
template<typename S,typename T>using pmat4=vector<vector<vector<vector<pair<S,T>>>>>;
template<typename... T>using tvec=vector<tuple<T...>>;
template<typename... T>using tmat=vector<vector<tuple<T...>>>;
template<typename... T>using tmat3=vector<vector<vector<tuple<T...>>>>;
template<typename... T>using tmat4=vector<vector<vector<vector<tuple<T...>>>>>;
#define rep(i, n) for(lint i = 0; i < (lint)(n); i++)
#define irep(i) for(lint i = 0;; i++)
#define irep1(i) for(lint i = 1;; i++)
#define irep2(i) for(lint i = 2;; i++)
#define rrep(i, n) for(lint i = (lint)(n-1); i >-1; i--)
#define rrepi(i,a,b) for(lint i = (lint)(b-1); i >a-1; i--)
#define repi(i,a,b) for(lint i=lint(a);i<lint(b);i++)
#define rep2(i,a,b,c) for(lint i=lint(a);i>lint(b);i+=c)
#define all(x) (x).begin(),(x).end()
#define dist(x1,y1,x2,y2) (pow(pow(x2-x1,2)+pow(y2-y1,2),0.5))
//#define input(a,n) lint n;cin>>n;vector<lint>a(n);rep(i,n)cin>>a[i];
#define SUM(v) accumulate(all(v),0LL)
#define INF (1LL<<60)
#define IINF (1<<30)
#define EPS (1e-10)
#define LINF 9223372036854775807
//#define MOD 998244353LL
//#define MOD 1000000007LL
#define MOD 65537LL
#define endl "\n"
template<typename T>inline void numout(T t){bool f=0;for(auto i:t){cout<<(f?" ":"")<<i<INF/2?i:"INF";f=1;}cout<<endl;}
template<typename T>inline void numout2(T t){for(auto i:t)numout(i);}
template<typename T>inline void output(T t){bool f=0;for(auto i:t){cout<<(f?" ":"")<<i;f=1;}cout<<endl;}
template<typename T>inline void output2(T t){for(auto i:t)output(i);}
template<typename T>inline void _output(T t){bool f=0;for(int i=0;i<t.size();i++){cout<<f?"":" "<<t[i];f=1;}cout<<endl;}
template<typename T>inline void _output2(T t){for(int i=0;i<t.size();i++)output(t[i]);}
auto Y=[&](auto f){return[&](auto... args){return f(f, args...);};};
template<typename T=lint>T in(){return *istream_iterator<T>(cin);}
template<typename T=lint>inline T gcd(T a,T b){return b?gcd(b,a%b):a;}
template<typename T=lint>inline T lcm(T a,T b){return a/gcd(a,b)*b;}
template<typename T>inline T minq(T a,T b){return min(a,b);}
template<typename T>inline T maxq(T a,T b){return max(a,b);}
inline bool chmin(auto& s,const auto& t){bool res=s>t;s=min(s,t);return res;}
inline bool chmax(auto& s,const auto& t){bool res=s<t;s=max(s,t);return res;}
const vector<lint> dx={-1,1,0,0,1,1,-1,-1};
const vector<lint> dy={0,0,-1,1,1,-1,1,-1};


template<typename T,typename E>
class lazy_segment_tree{
    template<typename Getter>
    class iterator{
        int i;
        Getter getter;
        public:
        iterator(const int& i,const Getter& getter):i(i),getter(getter){}
        inline auto operator*()noexcept{return getter(i);}
        inline constexpr iterator operator++()noexcept{++i;return *this;}
        inline constexpr iterator operator--()noexcept{--i;return *this;}
        inline constexpr iterator operator++(int n)noexcept{++i;return *this;}
        inline constexpr iterator operator--(int n)noexcept{--i;return *this;}
        inline constexpr iterator operator+=(const int& rhs)noexcept{i+=rhs;return *this;}
        inline constexpr iterator operator-=(const int& rhs)noexcept{i-=rhs;return *this;}
        inline constexpr iterator operator+(const int& rhs)const noexcept{return iterator(*this)+=rhs;}
        inline constexpr iterator operator-(const int& rhs)const noexcept{return iterator(*this)-=rhs;}
        inline constexpr bool operator!=(const iterator& rhs)const noexcept{return i!=rhs.i;}
        inline constexpr bool operator==(const iterator& rhs)const noexcept{return i==rhs.i;}
    };
    inline auto make_iterator(const int& i)noexcept{
        static auto getter=[this](const int& i){return get(i,i+1);};
        return iterator<decltype(getter)>(i,getter);
    }
    int n=1,sz;
    T* node;
    E* lazy;
    int ids[64];
    int idx;
    T et;E ee;
    void eval(const auto& t)noexcept{
        if(lazy[t]==ee)return;
        node[t]=h(node[t],lazy[t],n>>(int)(log2(t+1)));
        if(t<n-1){
            lazy[(t<<1)+1]=g(lazy[(t<<1)+1],lazy[t]);
            lazy[(t<<1)+2]=g(lazy[(t<<1)+2],lazy[t]);
        }
        lazy[t]=ee;
    }
    void get_eval(auto l,auto r)noexcept{
        l+=n;r+=n;
        const int lm=(l/(l&-l))>>1;
        const int rm=(r/(r&-r))>>1;
        idx=0;
        while(r>l){
            if(r<=rm&&r)ids[idx++]=r-1;
            if(l<=lm&&l)ids[idx++]=l-1;
            l>>=1;r>>=1;
        }
        while(l){
            ids[idx++]=l-1;
            l>>=1;
        }
    }
	public:
    lazy_segment_tree(const vector<T>& v,const T& et,const E& ee):sz(v.size()),et(et),ee(ee){
        while(n<v.size())n<<=1;
        node=new T[(n<<1)-1];
        lazy=new E[(n<<1)-1];
        for(int i=(int)v.size()+n-1;i<(n<<1)-1;i++)node[i]=et;
        for(int i=0;i<(n<<1)-1;i++)lazy[i]=ee;
        for(int i=0;i<(int)v.size();i++)node[i+n-1]=v[i];
        for(int i=n;i>=0;i--)node[i]=f(node[(i<<1)+1],node[(i<<1)+2]);
    }
    lazy_segment_tree(const auto& sz,const T& et,const E& ee):sz(sz),et(et),ee(ee){
        while(n<sz)n<<=1;
        node=new T[(n<<1)-1];
        lazy=new E[(n<<1)-1];
        for(int i=0;i<(n<<1)-1;i++)node[i]=et;
        for(int i=0;i<(n<<1)-1;i++)lazy[i]=ee;
    }
    constexpr void update(auto l,auto r,E val)noexcept{
        get_eval(l,r);
        for(int i=idx-1;i>=0;i--)eval(ids[i]);
        l+=n;r+=n;
        while(l<r){
            if(l&1){lazy[l-1]=g(lazy[l-1],val);eval(l-1);++l;}
            if(r&1){--r;lazy[r-1]=g(lazy[r-1],val);eval(r-1);}
            l>>=1;r>>=1;
        }
        for(int i=0;i<idx;i++){
            eval((ids[i]<<1)+1);
            eval((ids[i]<<1)+2);
            node[ids[i]]=f(node[(ids[i]<<1)+1],node[(ids[i]<<1)+2]);
        }
    }
    T get(auto l,auto r){
        get_eval(l,r);
        for(int i=idx-1;i>=0;i--)eval(ids[i]);
        l+=n;r+=n;
        T res=et;
        while(l<r){
            if(l&1){eval(l-1);res=f(res,node[l-1]);l++;}
            if(r&1){--r;eval(r-1);res=f(res,node[r-1]);}
            l>>=1;r>>=1;
        }
        return res;
    }
    inline auto begin()noexcept{return make_iterator(0);}
    inline auto end()noexcept{return make_iterator(sz);}
	private:
	T f(const T& a,const T& b){
		return update(a,b);
	}
	T h(const T& a,const E& b,const auto& sz){
		return update(a,b);
	}
	E g(const E& a,const E& b){
		return update(a,b);
	}
	auto update(auto a,auto b){return b==ee?a:b;}
};

int main(){
	lint n,q;
	cin>>n>>q;
	lazy_segment_tree<lint,lint> seg(n,(1LL<<31)-1,-1);
	rep(i,q){
		lint x;
		cin>>x;
		if(x){
			lint i;
			cin>>i;
			cout<<seg.get(i,i+1)<<endl;
		}else{
			lint s,t,u;
			cin>>s>>t>>u;
			seg.update(s,t+1,u);
		}
	}
}



Measured memory_bytes: 7296