50pts RE#6~10 求条

#include <bits/stdc++.h>
#define unsigned int long long
#define endl '\n'
using namespace std;
const int N = 1e6 + 5;
int a[N], lazy[n << 2];
struct node {
	int val, len;
} tree[N << 2];

node operator+(node l, node r) {
	return {l.val + r.val, l.len + r.len};
}

void push_down(int p) {
    if (lazy[p] == 0) return;
    tree[p << 1].val += tree[p << 1].len * lazy[p];
    tree[p << 1 | 1].val += tree[p << 1 | 1].len * lazy[p];
    lazy[p << 1] += lazy[p];
    lazy[p << 1 | 1] += lazy[p];
    lazy[p] = 0;
}


void build(int p, int l, int r) {
    if (l == r) {
        tree[p] = {a[l], 1};
        return;
    }
    int mid = (l + r) >> 1;
    build(p << 1, l, mid);
	build(p << 1 | 1, mid + 1, r);
    tree[p] = tree[p << 1] + tree[p << 1 | 1];
}

void update(int p, int l, int r, int ql, int qr, int k) {
	if (ql <= l and r <= qr) {
		tree[p].val += (r - l + 1) * k;
		lazy[p] += k;
		return;
	}
	push_down(p);
	int mid = (l + r) >> 1;
	if (ql <= mid) update(p << 1, l, mid, ql, qr, k);
	if (qr > mid) update(p << 1 | 1, mid + 1, r, ql, qr, k);
	tree[p] = tree[p << 1] + tree[p << 1 | 1];
}

node query(int p, int l, int r, int ql, int qr) {
	if (ql <= l and r <= qr) {
		return tree[p];
	}
	push_down(p);
	int mid = (l + r) >> 1;
	if (qr <= mid) {
		return query(p << 1, l, mid, ql, qr);
	}
	if (ql > mid) {
		return query(p << 1 | 1, mid + 1, r, ql, qr);
	}
	return query(p << 1, l, mid, ql, qr) + query(p << 1 | 1, mid + 1, r, ql, qr);
}

#undef int
int n, m;
void solve() {
	cin >> n >> m;
	for (int i = 1; i <= n; i++) a[i] = i;
	build(1, 1, n);
	while (m--) {
		int op;
		cin >> op;
		if (op == 1) {
			int l, r, k;
			cin >> l >> r >> k;
			update(1, 1, n, l, r, k);
		} else {
			int l, r;
			cin >> l >> r;
			cout << query(1, 1, n, l, r).val << endl;
		}
	}
}
int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	cout.tie(0);
	solve();
	return 0;
}