Binary Search on Segment Tree - Walk on tree

//Make CSP great again
//You're as beautiful as the day I lost you
#include <bits/stdc++.h>
#define TASK "TESTCODE"
using namespace std;
const int N = 1e5;
int n, a[N + 1], q;
struct SegmentTree
{
    int Tree[4 * N + 1];
    void BuildTree(int v, int TreeL, int TreeR)
    {
        if (TreeL == TreeR)
        {
            Tree[v] = a[TreeL];
            return ;
        }
        int mid = (TreeL + TreeR)/2;
        BuildTree(v * 2, TreeL, mid);
        BuildTree(v * 2 + 1, mid + 1, TreeR);
        Tree[v] = min(Tree[2 * v], Tree[2 * v + 1]);
    }
    void Update(int v, int TreeL, int TreeR, int pos, int val)
    {
        if (TreeL == TreeR)
        {
            Tree[v] = val;
            return ;
        }
        int mid = (TreeL + TreeR)/2;
        if (pos <= mid)
        {
            Update(v * 2, TreeL, mid, pos, val);
        }
        else
        {
            Update(v * 2 + 1, mid + 1, TreeR, pos, val);
        }
        Tree[v] = min(Tree[2 * v], Tree[2 * v + 1]);
    }
    int Query(int v, int TreeL, int TreeR, int u, int k)
    {
        if (Tree[v] > k || TreeR < u)
        {
            return - 1;
        }
        if (TreeL == TreeR)
        {
            return TreeL;
        }
        int mid = (TreeL + TreeR)/2;
        int res = -1;
        if (Tree[2 * v] <= k)
        {
            res = Query(v * 2, TreeL, mid, u, k);
        }
        if (res == -1)
        {
            res = Query(v * 2 + 1, mid + 1, TreeR, u, k);
        }
        return res;
    }
};
SegmentTree Tree;
void read()
{
    cin >> n >> q;
    for (int i = 1; i <= n; ++ i)
    {
        cin >> a[i];
    }
    Tree.BuildTree(1, 1, n);
}
void solve()
{
    while(q--)
    {
        int t;
        cin >> t;
        if (t == 2)
        {
            int u, v, k;
            cin >> u >> v >> k;
            int res = Tree.Query(1, 1, n, u, k);
            if (res > v || res == -1)
            {
                cout << "Skip";
            }
            else
            {
                cout << res;
            }
            cout << '\n';
        }
        else
        {
            int u, k;
            cin >> u >> k;
            Tree.Update(1, 1, n, u, k);
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(TASK".INP", "r"))
    {
        freopen(TASK".INP", "r", stdin);
        //freopen(TASK".OUT", "w", stdout);
    }
    int t = 1;
    bool typetest = false;
    if (typetest)
    {
        cin >> t;
    }
    for (int __ = 1; __ <= t; ++ __)
    {
        //cout << "Case " << __ << ": ";
        read();
        solve();
    }
}