求大佬指教

#include <iostream>
#include <cstdio>
using namespace std;

const long long MAXN = 1e5 + 5;
const long long INF = 0x3f3f3f3f;

long long n, m;
long long a[MAXN];

struct arp {
    long long l, r;
    long long start = 0;
    long long diff = 0;
    long long sumarp() {
        return ((start) + (start + (r - l) * diff)) * (r - l + 1) / 2;
    }
};

struct Node {
    long long left, right;
    long long lazyadd, sum;
    arp lazyarp;
    long long len() {
        return right - left + 1;
    }
    
};

Node t[4 * MAXN];

long long lson(long long id) {
    return id * 2;
}

long long rson(long long id) {
    return id * 2 + 1;
}

void update(long long id) {
    t[id].sum = t[lson(id)].sum + t[rson(id)].sum;
}

void pushdown(long long id) {
    /*
    if (t[id].lazyadd) {
        t[lson(id)].lazyadd += t[id].lazyadd;
        t[rson(id)].lazyadd += t[id].lazyadd;
        t[lson(id)].sum += t[lson(id)].lazyadd * t[lson(id)].len();
        t[rson(id)].sum += t[rson(id)].lazyadd * t[rson(id)].len();
        t[id].lazyadd = 0;
    }
    */
    if (t[id].lazyarp.diff) {
        t[lson(id)].lazyarp.start += t[id].lazyarp.start;
        t[lson(id)].lazyarp.diff += t[id].lazyarp.diff;
        t[lson(id)].sum += t[lson(id)].lazyarp.sumarp();
        
        t[rson(id)].lazyarp.start += (t[id].lazyarp.start + t[id].lazyarp.diff * (t[lson(id)].len() + 1));
        t[rson(id)].lazyarp.diff += t[id].lazyarp.diff;
        t[rson(id)].sum += t[rson(id)].lazyarp.sumarp();
        
        t[id].lazyarp.diff = 0;
        t[id].lazyarp.start = 0;
        
    }
}

void buildtree(long long id, long long l, long long r) {
    t[id].left = l;
    t[id].right = r;
    t[id].lazyarp.l = l;
    t[id].lazyarp.r = r;
    if (l == r) {
        t[id].sum = a[l];
        //cout << id << " " << t[id].sum << endl;
        return;
    }
    //cout << l << " " << r << endl;
    long long mid = (l + r) / 2;
    buildtree(lson(id), l, mid);
    buildtree(rson(id), mid + 1, r);
    update(id);
}

void change(long long id, long long l, long long r, arp c) {
    if (l <= t[id].left && t[id].right <= r) {
        //t[id].lazyadd += c.sumarp();
        t[id].lazyarp.diff += c.diff;
        t[id].lazyarp.start += c.start;
        t[id].sum += c.sumarp();
        //cout << "rfevds" << endl;
        return;
    }
    
	pushdown(id);
    long long mid = (t[id].left + t[id].right) / 2;
    //cout << "mid: " << mid << endl;

    if (l <= mid) change(lson(id), l, r, (arp){c.l, mid, c.start, c.diff});
    if (r > mid) change(rson(id), l, r, (arp){mid + 1, c.r, c.start + c.diff * (mid - c.l + 1), c.diff});
    update(id);
}

long long query(long long id, long long l, long long r) {
    long long ans = 0;
    if (l <= t[id].left && t[id].right <= r) {
        //cout << t[id].left << " " << t[id].right << " " << t[id].sum << endl;
        return t[id].sum;
    }
    pushdown(id);
    long long mid = (t[id].left + t[id].right) / 2;
    if (l <= mid) ans += query(lson(id), l, r);
    if (r > mid) ans += query(rson(id), l, r);
    update(id);
    return ans;
}

void printarp(arp c) {
    cout << c.l << " " << c.r << " " << c.start << " " << c.diff << endl;
    cout << c.sumarp();
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    
    cin >> n >> m;
    
    for (long long i = 1; i <= n; i++) {
        cin >> a[i];
    }
    arp test;

    test.start = 1;
    test.diff = 1;
    test.l = 1;
    test.r = 100;
    //cout << test.sumarp() << endl;
    //printarp((arp){4, 4, 5, 2});
    buildtree(1, 1, n);
    for (long long i = 1; i <= m; i++) {
        long long op;
        long long l, r, k, d;
        cin >> op;
        if (op == 1) {
            cin >> l >> r >> k >> d;
            change(1, l, r, (arp) {l, r, k, d});
        }
        if (op == 2) {
            cin >> l;
            cout << query(1, l, l) << endl;
        }
    }
    //cout << query(1, 4, 4) << endl;
    return 0;
}