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| /* | |
| * Created by Dipta Das on 23-11-2018 | |
| * Title: Segment Tree Lazy Propagation | |
| * Artical by Shafayet Bhai: http://www.shafaetsplanet.com/planetcoding/?p=1591, http://www.shafaetsplanet.com/?p=1557 | |
| * Solution: https://gist.github.com/dipta10/ac694515d7370ce3ae56754a8a3f119e | |
| * Comments: | |
| */ | |
| #include <bits/stdc++.h> | |
| #include <stdio.h> | |
| #define fin freopen("input", "r", stdin) | |
| #define whatis(x) cerr << #x << ": " << x << endl; | |
| #define mx 10000 | |
| using namespace std; | |
| using ll = long long; | |
| ll arr[mx]; | |
| struct info { | |
| ll prop, sum; | |
| } tree[mx * 4]; | |
| void init(int node, int b, int e) | |
| { | |
| if (b == e) { | |
| tree[node].sum = arr[b]; | |
| return; | |
| } | |
| int Left = node * 2; | |
| int Right = node * 2 + 1; | |
| int mid = (b + e) / 2; | |
| init(Left, b, mid); | |
| init(Right, mid + 1, e); | |
| tree[node].sum = tree[Left].sum + tree[Right].sum; | |
| } | |
| void update(int node, int b, int e, int i, int j, ll x) | |
| { | |
| if (i > e || j < b) | |
| return; | |
| if (b >= i && e <= j) | |
| { | |
| tree[node].sum += ((e - b + 1) * x); | |
| tree[node].prop += x; | |
| return; | |
| } | |
| int Left = node * 2; | |
| int Right = (node * 2) + 1; | |
| int mid = (b + e) / 2; | |
| update(Left, b, mid, i, j, x); | |
| update(Right, mid + 1, e, i, j, x); | |
| tree[node].sum = tree[Left].sum + tree[Right].sum + (e - b + 1) * tree[node].prop; | |
| } | |
| ll query(int node, int b, int e, int i, int j, ll carry = 0) | |
| { | |
| if (i > e || j < b) | |
| return 0; | |
| if (b >= i and e <= j) | |
| return tree[node].sum + carry * (e - b + 1); | |
| int Left = node << 1; | |
| int Right = (node << 1) + 1; | |
| int mid = (b + e) >> 1; | |
| ll p1 = query(Left, b, mid, i, j, carry + tree[node].prop); | |
| ll p2 = query(Right, mid + 1, e, i, j, carry + tree[node].prop); | |
| return p1 + p2; | |
| } | |
| int main() { | |
| // ios_base::sync_with_stdio(false); | |
| // cin.tie(NULL); | |
| int n; | |
| cin >> n; | |
| for (int i = 1; i < n; ++i) { | |
| cin >> arr[i]; | |
| } | |
| init(1, 1, 7); | |
| update(1, 1, 7, 1, 7, 2); | |
| update(1, 1, 7, 1, 4, 3); | |
| cout << "Value for range [1, 1]: " << query(1, 1, 7, 1, 4) << "\n\n"; | |
| cout << "State of Segment Tree:\n"; | |
| for (int i = 1; i < 14; ++i) { | |
| cout << "index: " << i << " sum: " << tree[i].sum << " prop: " << tree[i].prop << "\n"; | |
| } | |
| return 0; | |
| } | |
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