// #pragma GCC optimize("Ofast,unroll-loops")
// #pragma GCC target("avx,avx2,fma")

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

#define ll long long
#define ull unsigned long long
#define dd double
#define ld long double
#define sl(n) scanf("%lld", &n)
#define si(n) scanf("%d", &n)
#define sd(n) scanf("%lf", &n)
#define pll pair <ll, ll>
#define pii pair <int, int>
#define mp make_pair
#define pb push_back
#define all(v) v.begin(), v.end()
#define inf (1LL << 61)
#define loop(i, start, stop, inc) for(ll i = start; i <= stop; i += inc)
#define for1(i, stop) for(ll i = 1; i <= stop; ++i)
#define for0(i, stop) for(ll i = 0; i < stop; ++i)
#define rep1(i, start) for(ll i = start; i >= 1; --i)
#define rep0(i, start) for(ll i = (start-1); i >= 0; --i)
#define ms(n, i) memset(n, i, sizeof(n))
#define casep(n) printf("Case %lld:", ++n)
#define pn printf("\n")
#define pf printf
#define EL '\n'
#define fastio std::ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);

const ll sz = 22, MAX_N = (1<<14)+10, psz = 4*MAX_N + MAX_N*14, lim = 6;
ll ara[sz], n, idx, tot, l, r;

ll tr[psz], Left[psz], Right[psz], root[MAX_N], sufSub[MAX_N], idn;
vector <ll> num;

void build(ll lo, ll hi, ll node)
{
    if(lo == hi) {
        tr[node] = 0;
        return;
    }

    int mid = lo+hi>>1;
    Left[node] = ++idn, Right[node] = ++idn;

    build(lo, mid, Left[node]);
    build(mid+1, hi, Right[node]);

    tr[node] = 0;
}

ll upd(ll lo, ll hi, ll indx, ll node)
{
    if(lo > indx || hi < indx)
        return node;

    ll nnode = ++idn;

    if(lo == hi) {
        tr[nnode] = tr[node]+1;
        return nnode;
    }

    int mid = lo+hi>>1;

    Left[nnode] = upd(lo, mid, indx, Left[node]);
    Right[nnode] = upd(mid+1, hi, indx, Right[node]);

    tr[nnode] = tr[ Left[nnode] ] + tr[ Right[nnode] ];
    return nnode;
}

ll query(ll lo, ll hi, ll l, ll r, ll lnode, ll rnode)
{
    if(lo > r || hi < l)
        return 0;

    if(lo >= l && hi <= r)
        return tr[rnode] - tr[lnode];

    int mid = lo+hi>>1;

    return query(lo, mid, l, r, Left[lnode], Left[rnode])
        +  query(mid+1, hi, l, r, Right[lnode], Right[rnode]);
}

ll solve(ll pos, ll sum, ll x)
{
    if(pos > min(n, lim))
        return 0;

    ll nsum = sum+ara[pos], ret = 0;
    tot++;

    if(tot >= l && tot <= r)
        ret += (nsum <= x);

    ret += solve(pos+1, nsum, x);

    if(nsum <= x) {
        ll start = max(1LL, l-tot), stop = min(idx, r-tot);
        ll xp = upper_bound(all(num), x-nsum) - num.begin();

        if(start <= stop)
            ret += query(0, idx, 0, xp, root[start-1], root[stop]);
    }

    tot += idx;

    ret += solve(pos+1, sum, x);

    return ret;
}

void solve2(ll pos, ll sum)
{
    if(pos > n)
        return;

    sufSub[++idx] = sum+ara[pos];

    solve2(pos+1, sum+ara[pos]);
    solve2(pos+1, sum);
}

void makeSufSub()
{
    solve2(lim+1, 0);

    for1(i, idx) num.pb(sufSub[i]);

    sort(all(num));
    num.erase(unique(all(num)), num.end());

    root[0] = ++idn;
    build(0, idx, root[0]);

    for1(i, idx) {
        ll pos = upper_bound(all(num), sufSub[i]) - num.begin();
        root[i] = upd(0, idx, pos, root[i-1]);
    }
}

ll countLeq(ll x)
{
    tot = 0;
    ll ret = solve(1, 0, x);

    ll start = max(1LL, l-tot), stop = min(idx, r-tot);

    if(start <= stop) {
        ll xp = upper_bound(all(num), x) - num.begin();
        ret += query(0, idx, 0, xp, root[start-1], root[stop]);
    }

    return ret;
}

ll findk(ll k)
{
    ll lo = 1, hi = n*(ll)1e9, ret;

    while(lo <= hi) {
        ll mid = lo+hi >> 1;

        ll got = countLeq(mid);

        if(got >= k) {
            ret = mid;
            hi = mid-1;
        }
        else
            lo = mid+1;
    }

    return ret;
}

int main()
{
    ll q;
    cin >> n >> q;

    for1(i, n) {
        sl(ara[i]);
    }

    if(n > lim)
        makeSufSub();

    while(q--) {
        ll typ; sl(typ);

        if(typ == 1) {
            ll k, c;
            sl(k), sl(c);

            ara[k] = c;
        }
        else {
            ll k;
            sl(l), sl(r), sl(k);

            pf("%lld\n", findk(k));
        }
    }

    return 0;
}