Create SegmentTree.cpp

c++/SegmentTree.cpp

@@ -0,0 +1,115 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+#include <ext/pb_ds/assoc_container.hpp>
+#include <ext/pb_ds/tree_policy.hpp>
+using namespace __gnu_pbds;
+template <typename T> using ordered_set = tree<T, null_type,less<T>, rb_tree_tag,tree_order_statistics_node_update>;
+// orderded_set ->  find_by_order(x)<itr, x being 0-indexed>; order_of_key(x)<count, strictly less>
+
+typedef long long       ll;
+typedef long double     lld;
+typedef pair<int, int>  pii;
+typedef pair<ll, ll>    pll;
+#define loop(n)         for(ll i = 0; i < (n); ++i)
+#define rep(i,zz,n)     for(ll i = zz; i < (n); ++i)
+#define repi(i,zz,n)    for(ll i = zz; i >= (n); --i)
+#define all(v)          v.begin(),v.end()
+#define pb              push_back
+#define ff              first
+#define ss              second
+#define sz(x)           (int)x.size()
+#define nline           cout << '\n'
+
+#define     debug(x)    cout << #x << " "; _print(x); cout << '\n';
+#define     _debug(a,b) cout << #a << " [ "; array_debug(a,b); cout << "]\n";
+template <class T, class V> void array_debug(T *a, V n){ rep(i,0,n) cout << a[i] << ' ';}
+template <class T>          void _print(T t) {cout << t;}
+template <class T, class V> void _print(pair <T, V> p) {cout << "{"; _print(p.ff); cout << ","; _print(p.ss); cout << "}";}
+template <class T>          void _print(vector <T> v) {cout << "[ "; for (T i : v) {_print(i); cout << " ";} cout << "]";}
+template <class T>          void _print(set <T> v) {cout << "[ "; for (T i : v) {_print(i); cout << " ";} cout << "]";}
+template <class T>          void _print(multiset <T> v) {cout << "[ "; for (T i : v) {_print(i); cout << " ";} cout << "]";}
+template <class T, class V> void _print(map <T, V> v) {cout << "[ "; for (auto i : v) {_print(i); cout << " ";} cout << "]";}
+
+const lld eps = 1e-9;
+const int mod = 1e9 + 7;
+const ll inf = 1e18;
+const int N1 = 2e5 + 10;
+
+template<typename T>
+struct SegmentTree{
+	vector<T> st;
+	void assign(vector<int> &v1) {
+		int n = sz(v1);
+		st = vector<T>(4 * n + 1);
+		build(v1, 1, 0, n - 1);
+	}
+	T combine(T x, T y) {
+		// T z;
+		// return z;
+		return { x.sum + y.sum }; // check which opeartion is to be performed
+	}
+	void build(vector<int>& v1, int v, int tl, int tr) {
+		if (tl == tr) {
+			st[v].sum = v1[tl]; //  check
+		}
+		else{
+			int mid = (tl + tr) / 2;
+			build(v1, 2 * v, tl, mid);
+			build(v1, 2 * v + 1, mid + 1, tr);
+			st[v] = combine(st[2 * v], st[2 * v + 1]);
+		}
+	}
+	// tl, tr   : the current segment/range whose node/vertex is v
+	//  l,  r   : the segment/range on which the 'range query' is to be performed
+	T query(int v, int tl, int tr, int l, int r) {
+		if (tr < l || r < tl) {
+			return { 0 }; // check which opeartion is to be performed
+		}
+		else if (tl == l && tr == r) {
+			return st[v];
+		}
+		int mid = (tl + tr) / 2;
+		return combine(query(2 * v, tl, mid, l, min(r, mid)), query(2 * v + 1, mid + 1, tr, max(l, mid + 1), r));
+	}
+	void update_one(int v, int tl, int tr, int pos, int newVal) {
+		if (tl == tr) {
+			st[v].sum = newVal;
+			// check whether the newVal is added or updated
+			return;
+		}
+		int mid = (tl + tr) / 2;
+		if (pos <= mid) {
+			update_one(2 * v, tl, mid, pos, newVal);
+		}
+		else{
+			update_one(2 * v + 1, mid + 1, tr, pos, newVal);
+		}
+		st[v] = combine(st[2 * v], st[2 * v + 1]);
+	}
+};
+struct Node{
+	int sum;
+};
+SegmentTree<Node> seg;
+
+int code() {
+
+	// enter main code here
+
+	return 0;
+}
+
+int main() {
+	ios::sync_with_stdio(0); cin.tie(0);
+	// freopen("input.txt","r",stdin);
+	// freopen("output.txt","w",stdout);
+
+	int tc = 1;
+	cin >> tc;
+
+	loop(tc)  code();
+	// rep(i, 1, tc + 1)  cout << "Case #" << i << ": ", code();
+
+	return 0;
+}