mirror of
https://git.sb/baoshuo/OI-codes.git
synced 2024-11-24 09:48:48 +00:00
108 lines
2.7 KiB
C++
108 lines
2.7 KiB
C++
#include <bits/stdc++.h>
|
|
|
|
using namespace std;
|
|
|
|
struct node {
|
|
int l, r;
|
|
double s, s2, d;
|
|
|
|
node() {
|
|
l = r = 0;
|
|
s = s2 = d = 0.00;
|
|
}
|
|
node(int _l, int _r) {
|
|
l = _l;
|
|
r = _r;
|
|
s = s2 = d = 0.00;
|
|
}
|
|
} tr[100005 << 2];
|
|
int n, m, op, x, y;
|
|
double k, a[100005];
|
|
|
|
void pushup(int u) {
|
|
tr[u].s = tr[u << 1].s + tr[u << 1 | 1].s;
|
|
tr[u].s2 = tr[u << 1].s2 + tr[u << 1 | 1].s2;
|
|
}
|
|
|
|
void pushdown(int u) {
|
|
if (!tr[u].d) return;
|
|
tr[u << 1].d += tr[u].d;
|
|
tr[u << 1 | 1].d += tr[u].d;
|
|
tr[u << 1].s2 += tr[u << 1].s * tr[u].d * 2 + (tr[u << 1].r - tr[u << 1].l + 1) * tr[u].d * tr[u].d;
|
|
tr[u << 1 | 1].s2 += tr[u << 1 | 1].s * tr[u].d * 2 + (tr[u << 1 | 1].r - tr[u << 1 | 1].l + 1) * tr[u].d * tr[u].d;
|
|
tr[u << 1].s += (tr[u << 1].r - tr[u << 1].l + 1) * tr[u].d;
|
|
tr[u << 1 | 1].s += (tr[u << 1 | 1].r - tr[u << 1 | 1].l + 1) * tr[u].d;
|
|
tr[u].d = 0;
|
|
}
|
|
|
|
void build(int u, int l, int r) {
|
|
tr[u] = node(l, r);
|
|
if (l == r) {
|
|
tr[u].s = a[l];
|
|
tr[u].s2 = a[l] * a[l];
|
|
return;
|
|
}
|
|
int mid = l + r >> 1;
|
|
build(u << 1, l, mid);
|
|
build(u << 1 | 1, mid + 1, r);
|
|
pushup(u);
|
|
}
|
|
|
|
double query(int u, int l, int r) {
|
|
if (l <= tr[u].l && tr[u].r <= r) {
|
|
return tr[u].s;
|
|
}
|
|
int mid = tr[u].l + tr[u].r >> 1;
|
|
double s = 0.00;
|
|
pushdown(u);
|
|
if (l <= mid) s += query(u << 1, l, r);
|
|
if (r > mid) s += query(u << 1 | 1, l, r);
|
|
return s;
|
|
}
|
|
|
|
double query2(int u, int l, int r) {
|
|
if (l <= tr[u].l && tr[u].r <= r) {
|
|
return tr[u].s2;
|
|
}
|
|
int mid = tr[u].l + tr[u].r >> 1;
|
|
double s = 0.00;
|
|
pushdown(u);
|
|
if (l <= mid) s += query2(u << 1, l, r);
|
|
if (r > mid) s += query2(u << 1 | 1, l, r);
|
|
return s;
|
|
}
|
|
|
|
void modify(int u, int l, int r, double d) {
|
|
if (l <= tr[u].l && tr[u].r <= r) {
|
|
tr[u].d += d;
|
|
tr[u].s2 += tr[u].s * d * 2 + (tr[u].r - tr[u].l + 1) * d * d;
|
|
tr[u].s += (tr[u].r - tr[u].l + 1) * d;
|
|
return;
|
|
}
|
|
int mid = tr[u].l + tr[u].r >> 1;
|
|
pushdown(u);
|
|
if (l <= mid) modify(u << 1, l, r, d);
|
|
if (r > mid) modify(u << 1 | 1, l, r, d);
|
|
pushup(u);
|
|
}
|
|
|
|
int main() {
|
|
cin >> n >> m;
|
|
for (int i = 1; i <= n; i++) {
|
|
cin >> a[i];
|
|
}
|
|
build(1, 1, n);
|
|
for (int i = 0; i < m; i++) {
|
|
cin >> op >> x >> y;
|
|
if (op == 1) {
|
|
cin >> k;
|
|
modify(1, x, y, k);
|
|
} else if (op == 2) {
|
|
cout << fixed << setprecision(4) << (double)query(1, x, y) / (y - x + 1) << endl;
|
|
} else if (op == 3) {
|
|
cout << fixed << setprecision(4) << (double)(query2(1, x, y) / ((y - x + 1) * 1.00)) - pow(query(1, x, y) / ((y - x + 1) * 1.00), 2) << endl;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|