线段树 ：区间修改，区间查询

题目描述

思路

代码

#include <cstdio>
#include <cstring>
long long n, m;
struct {
	long long at[1000005], arr[1000005 << 2], ad[1000005 << 2];
	void build(int k, int l, int r) {
		if (l == r) {
			arr[k] = at[l];
			return;
		}
		int mid = l + r >> 1;
		this->build(k << 1, l, mid);
		this->build(k << 1 | 1, mid + 1, r);
		arr[k] = arr[k << 1] + arr[k << 1 | 1];
	}
	void change(int k, int l, int r, int x, int y, int v) {
		if (x <= l && r <= y) {
			this->add(k, l, r, v);
			return;
		}
		int mid = l + r >> 1;
		this->pushdown(k, l, r, mid);
		if (x <= mid) this->change(k << 1, l, mid, x, y, v);
		if (y > mid) this->change(k << 1 | 1, mid + 1, r, x, y, v);
		arr[k] = arr[k << 1] + arr[k << 1 | 1]; 
	}
	long long query(int k, int l, int r, int x, int y) {
		if (x <= l && r <= y) return arr[k];
		long long res = 0;
		int mid = l + r >> 1;
		this->pushdown(k, l, r, mid);
		if (x <= mid) res += this->query(k << 1, l, mid, x, y);
		if (y > mid) res += this->query(k << 1 | 1, mid + 1, r, x, y);
		return res;
	}
	void add(int k, int l, int r, int v) {
		ad[k] += v;
		arr[k] += (long long)(r - l + 1) * v;
	}
	void pushdown(int k, int l, int r, int mid) {
		if (ad[k] == 0) return;
		add(k << 1, l, mid, ad[k]);
		add(k << 1 | 1, mid + 1, r, ad[k]);
		ad[k] = 0;
	}
} t;

inline long long read() {
	long long s = 0, f = 1;
	char ch = getchar();
	while (ch < '0' || ch > '9') {
		if (ch == '-') f = -1;
		ch = getchar();
	}
	while (ch >= '0' && ch <= '9') s = s * 10 + ch - '0', ch = getchar();
	return s * f;
}
int main() {
	n = read(), m = read();
	for (register int i = 1; i <= n; ++i) t.at[i] = read();
	t.build(1, 1, n);
	for (register int i = 1, a, b, c, d; i <= m; ++i) {
		a = read();
		if (a == 1) {
			b = read(), c = read(), d = read();
			t.change(1, 1, n, b, c, d);
		} else {
			b = read(), c = read();
			printf("%lld\n", t.query(1, 1, n, b, c));
		}
	}
	return 0;
}