update

Author: yashsiwach

CP Templetes/Graphs/adj matrix to adjlist.cpp

@@ -0,0 +1,17 @@
+vector<vector<int>> toadjlist(vector<vector<int>>&adj)
+{
+ int n=adj.size();
+ vector<vector<int>>adjlist(n);
+ for(int i=0;i<n;i++)
+ {
+ for(int j=0;j<n;j++)
+ {
+ if(adj[i][j]==1)
+ {
+ adjlist[i].push_back(j);
+ adjlist[j].push_back(i);
+ }
+ }
+ }
+ return adjlist;
+}

CP Templetes/trees/treebuilds.cpp

@@ -0,0 +1,99 @@
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long ll;
+#define MOD 1000000007
+#define pb push_back
+#define ppb pop_back
+#define ff first
+#define ss second
+#define PI 3.141592653589793238462
+#define set_bits __builtin_popcountll
+#define all(x) (x).begin(), (x).end()
+#define debug(x) cerr<<x<<" ";
+class node{
+int val;
+node*left;
+node*right;
+node(int val)
+{
+this->val=val;
+this->left=nullptr;
+this->right=nullptr;
+}
+}
+node* buildtree(int n,vector<int>&v)
+{
+queue<node*>q;
+node*root=new node(v[0]);
+q.push(root);
+int i=1;
+while(i<n&&!q.empty())
+{
+node*temp=q.front();
+q.pop();
+if(v[i]!=-1)
+{
+temp->left=new node(v[i]);
+q.push(temp->left);
+}
+i++;
+
+if(i<n)
+{
+if(v[i]!=-1)
+{
+temp->right=new node(v[i]);
+q.push(temp->right);
+}
+i++;
+}
+
+}
+return root;
+}
+void levelordertreversal(node*root)
+{
+queue<node*>q;
+q.push(root);
+q.push(NULL);
+while(!q.empty())
+{
+node*temp=q.front();
+q.pop();
+if(temp==NULL)
+{
+cout<<endl;
+if(!q.empty())
+{
+q.push(NULL);
+}
+}
+else
+{
+cout<<root->val<<" ";
+if(root->left)
+{
+q.push(root->left);
+}
+if(root->right){
+q.push(root->right);
+}
+
+}
+}
+}
+int main()
+{
+ int n;
+ cin>>n;
+ vector<int>v;
+ while(n!=-1)
+ {
+	v.push_back(n);
+	cin>>n;
+ }
+ v.push_back(-1);
+ node*root=buildtree(v.size(),v);
+ levelordertreversal(root);
+}
+

Important.txt

@@ -13,3 +13,4 @@
 13->int set/map we use upper and lower bound diff as set.upper_bound(3); in vector upper_bound(v.begin(),v.end(),target);because working in vector is BS and in set its tree
 14->int sum=accumulate(v.begin(),v.end(),0(initial sum value)); to get sum of vector;
 //7986952804
+sweepline adhoc