Uploaded new files

Author: ReetuRaj7

StaticQueries/RangeSumQueries.cpp renamed to RangeQueries/RangeSumQueries.cpp

@@ -0,0 +1,46 @@
+//Thursday 13-January-2022 21:16:42
+#include <bits/stdc++.h>
+//@ReetuRaj77
+#define lli long long int
+#define ulli unsigned long long int
+
+#define all(x) (x).begin(),(x).end()
+#define MAXN 200005
+#define fastio ios_base::sync_with_stdio(false);cin.tie(nullptr)
+
+using namespace std;
+
+int logs[MAXN + 5];
+int st[MAXN][30];
+
+int main() {
+	fastio;
+	int n, q;
+	cin >> n >> q;
+	logs[1] = 0;
+	for (int i = 2; i <= MAXN ; i++)logs[i] = logs[i / 2] + 1;
+	vector<int>a(n);
+	for (int i = 0; i < n; i++)cin >> a[i];
+	int K = 25;
+
+	//sparse table calculation
+	for (int i = 0; i < n; i++)
+		st[i][0] = a[i];
+	for (int j = 1; j <= K; j++) {
+		for (int i = 0; i + (1 << j) <= n; i++) {
+			st[i][j] = min(st[i][j - 1], st[i + (1 << (j - 1))][j - 1]);
+		}
+	}
+	//using sparse table to calculate the corresponding RMQs
+	//the idea is to think that we can divide an interval into
+	//parts of power of two..
+
+	for (int i = 0; i < q; i++) {
+		int L, R;
+		cin >> L >> R;
+		int j = logs[R - L + 1]; //to calculate nearest power of two, to start
+
+		int min_range = min(st[L - 1][j], st[R - (1 << j)][j]);
+		cout << min_range << endl;
+	}
+}

RangeQueries/Static_Range_Minimum_Queries.cc

@@ -0,0 +1,44 @@
+//Tuesday 11-January-2022 11:49:02
+#include <bits/stdc++.h>
+//@ReetuRaj77
+#define lli long long int
+#define ulli unsigned long long int
+
+#define all(x) (x).begin(),(x).end()
+
+#define fastio ios_base::sync_with_stdio(false);cin.tie(nullptr)
+
+using namespace std;
+
+vector<vector<int>>adj(200005, vector<int>());
+int dfs(int ch, int par, lli& res) {
+	vector<lli>ans;
+	for (auto x : adj[ch]) {
+		if (x != par) {
+			ans.push_back(dfs(x, ch, res));
+		}
+	}
+	if (ans.size() == 0)return 0;
+	sort(all(ans), greater<lli>());
+	lli t = ans.front();
+	if (ans.size() >= 2)
+		res = max(res, ans[1] + ans[0] + 2);
+	else
+		res = max(res, t + 1);
+	return 1 + t;
+
+}
+int main() {
+	fastio;
+	int n;
+	cin >> n;
+	for (int i = 0; i < n - 1; i++) {
+		int x, y;
+		cin >> x >> y;
+		adj[x].push_back(y);
+		adj[y].push_back(x);
+	}
+	lli res = 0;
+	int t = dfs(1, 0, res);
+	cout << res << endl;
+}

TreeAlgorithms/DiameterOfTree.cc

@@ -0,0 +1,39 @@
+//Saturday 15-January-2022 11:22:42
+#include <bits/stdc++.h>
+//@ReetuRaj77
+#define lli long long int
+#define ulli unsigned long long int
+
+#define all(x) (x).begin(),(x).end()
+
+#define fastio ios_base::sync_with_stdio(false);cin.tie(nullptr)
+
+using namespace std;
+
+vector<vector<int>>adj(200005, vector<int>());
+int subor[200005];
+int dfs(int src, int parent) {
+	int cur = 1;
+	for (auto A : adj[src]) {
+		if (A != parent) {
+			cur += dfs(A, src);
+		}
+	}
+	return subor[src] = cur;
+}
+int main() {
+	fastio;
+	int n;
+	cin >> n;
+	for (int i = 2; i <= n; i++) {
+		int x;
+		cin >> x;
+		adj[x].push_back(i);
+		adj[i].push_back(x);
+	}
+	subor[1] = dfs(1, 0);
+	for (int i = 1; i <= n; i++) {
+		cout << subor[i] - 1 << " ";
+	}
+	return 0;
+}

TreeAlgorithms/Subordinates.cpp

@@ -0,0 +1,42 @@
+//Friday 17-December-2021 23:38:07
+#include <bits/stdc++.h>
+//@ReetuRaj77
+#define lli long long int
+#define ulli unsigned long long int
+
+#define all(x) (x).begin(),(x).end()
+
+#define fastio ios_base::sync_with_stdio(false);cin.tie(nullptr)
+
+using namespace std;
+vector<vector<int>>adj(200005, vector<int>());
+int ans = 0;
+bool marked[200005] = {false};
+
+void parenting_dfs(int source, int parent) {
+	for (int i = 0; i < adj[source].size(); i++) {
+		if (adj[source][i] != parent) {
+			parenting_dfs(adj[source][i], source);
+		}
+	}
+	if (!marked[source] && !marked[parent] && parent != 0) {
+		ans ++;
+		marked[source] = marked[parent] = true;
+	}
+}
+
+int main() {
+	fastio;
+	int n;
+	cin >> n;
+
+	for (int i = 0; i < n - 1; i++) {
+		int x, y;
+		cin >> x >> y;
+		adj[x].push_back(y);
+		adj[y].push_back(x);
+	}
+
+	parenting_dfs(1, 0);
+	cout << ans << endl;
+}