Merge pull request #766 from Manda303/main

Max and min element in Binary Tree.cpp

Author: Sirajmolla

Queue using two Stacks.cpp

@@ -0,0 +1,86 @@
+#include<bits/stdc++.h>
+
+using namespace std;
+
+class StackQueue{
+private:
+    stack<int> s1;
+    stack<int> s2;
+public:
+    void push(int B);
+    int pop();
+
+};
+int main()
+{
+
+    int T;
+    cin>>T;
+    while(T--)
+    {
+        StackQueue *sq = new StackQueue();
+
+        int Q;
+        cin>>Q;
+        while(Q--){
+        int QueryType=0;
+        cin>>QueryType;
+        if(QueryType==1)
+        {
+            int a;
+            cin>>a;
+            sq->push(a);
+        }else if(QueryType==2){
+            cout<<sq->pop()<<" ";
+
+        }
+        }
+        cout<<endl;
+    }
+
+
+}
+// } Driver Code Ends
+
+
+/* The structure of the class is
+class StackQueue{
+private:   
+    // These are STL stacks ( http://goo.gl/LxlRZQ )
+    stack<int> s1;
+    stack<int> s2;
+public:
+    void push(int);
+    int pop();
+}; */
+
+/* The method push to push element into the queue */
+void StackQueue :: push(int x)
+ {
+        // Your Code
+        while(!s1.empty())
+        {
+            s2.push(s1.top());
+            s1.pop();
+        }
+        s1.push(x);
+        while(!s2.empty())
+        {
+            s1.push(s2.top());
+            s2.pop();
+        }
+            
+ }
+
+/*The method pop which return the element poped out of the queue*/
+int StackQueue :: pop()
+{
+        // Your Code     
+        int val=-1;
+        if(!s1.empty())
+        {
+            val=s1.top();
+            s1.pop();
+        }
+        return val;
+}

binary-tree/Max and min element in Binary Tree.cpp

@@ -0,0 +1,128 @@
+#include<bits/stdc++.h>
+using namespace std;
+
+// A tree node
+struct node
+{
+	int data;
+	struct node *left;
+	struct node *right;
+	
+	node(int x){
+	    data = x;
+	    left = NULL;
+	    right = NULL;
+	}
+};
+
+// Returns maximum value in a given Binary Tree
+int findMax(struct node* root);
+// Returns minimum value in a given Binary Tree
+int findMin(struct node* root);
+
+void insert(struct node *root,int n1,int n2,char lr)
+ {
+     if(root==NULL)
+        return;
+     if(root->data==n1)
+     {
+         switch(lr)
+         {
+          case 'L': root->left=new node(n2);
+                    break;
+          case 'R': root->right=new node(n2);
+                    break;
+         }
+     }
+     else
+     {
+         insert(root->left,n1,n2,lr);
+         insert(root->right,n1,n2,lr);
+     }
+ }
+// Driver program to test above functions
+int main()
+{
+    int t;
+    cin>>t;
+    while(t--)
+    {
+    int n;
+    cin>>n;
+    struct node *root=NULL;
+    while(n--)
+    {
+        char lr;
+        int n1,n2;
+        cin>>n1>>n2;
+        cin>>lr;
+        if(root==NULL)
+        {
+            root=new node(n1);
+            switch(lr){
+                    case 'L': root->left=new node(n2);
+                    break;
+                    case 'R': root->right=new node(n2);
+                    break;
+                    }
+        }
+        else
+        {
+            insert(root,n1,n2,lr);
+        }
+    }
+
+    cout<<findMax(root)<<" "<<findMin(root)<<endl;
+    }
+    return 0;
+}
+// } Driver Code Ends
+
+
+// Returns maximum value in a given Binary Tree
+int findMax(struct node* root)
+{
+// Your code goes here
+    queue <node *> q;
+    q.push(root);
+    int m=INT_MIN;
+    while(!q.empty())
+    {
+        int count=q.size(),sum=0;
+        for(int i=0;i<count;i++)
+        {
+            node *cur=q.front();
+            m=max(cur->data,m);
+            q.pop();
+            if(cur->left!=NULL)
+                q.push(cur->left);
+            if(cur->right!=NULL)
+                q.push(cur->right);
+        }
+    }
+    return m;
+}
+
+// Returns minimum value in a given Binary Tree
+int findMin(struct node* root)
+{
+// Your code goes here
+    queue <node *> q;
+    q.push(root);
+    int m=INT_MAX;
+    while(!q.empty())
+    {
+        int count=q.size(),sum=0;
+        for(int i=0;i<count;i++)
+        {
+            node *cur=q.front();
+            m=min(cur->data,m);
+            q.pop();
+            if(cur->left!=NULL)
+                q.push(cur->left);
+            if(cur->right!=NULL)
+                q.push(cur->right);
+        }
+    }
+    return m;
+}