Segment Tree 3

void push(vector<int>& t, int v) {
    if (t[v] != -1) {
        t[v * 2 + 1] = t[v];
        t[v * 2 + 2] = t[v];
        t[v] = -1;
    }
}

void build(vector<int>& a, vector<int>& t, int v, int tl, int tr) {
    if (tl == tr)
        t[v] = a[tl];
    else {
        int tm = (tl + tr) / 2;
        build(a, t, v * 2 + 1, tl, tm);
        build(a, t, v * 2 + 2, tm + 1, tr);
    }
}

void update(vector<int> &t, int v, int tl, int tr, int l, int r, int color) {
    if (l > r)
        return;
    if (l == tl && r == tr)
        t[v] = color;
    else {
        push(t, v);
        int tm = (tl + tr) / 2;
        update(t, v * 2 + 1, tl, tm, l, min(tm, r), color);
        update(t, v * 2 + 2, tm + 1, tr, max(tm + 1, l), r, color);
    }
}

int get(vector<int>& t, int v, int tl, int tr, int pos) {
    if (tl == tr)
        return t[v];
    push(t, v);
    int tm = (tl + tr) / 2;
    if (pos <= tm)
        return get(t, v * 2 + 1, tl, tm, pos);
    else
        return get(t, v * 2 + 2, tm + 1, tr, pos);
}