Added Euler Tour

Trees algorithm/EulerTour.cpp

@@ -0,0 +1,61 @@
+//snehal kumar
+
+#include <bits/stdc++.h> 
+using namespace std; 
+
+#define MAX 1001 
+
+// Adjacency list representation of tree 
+vector<int> adj[MAX];  
+
+// Visited array to keep track visited  
+// nodes on tour 
+int vis[MAX];  
+
+// Array to store Euler Tour 
+int Euler[2 * MAX];  
+
+// Function to add edges to tree 
+void add_edge(int u, int v) 
+{ 
+    adj[u].push_back(v); 
+    adj[v].push_back(u); 
+} 
+
+// Function to store Euler Tour of tree 
+void eulerTree(int u, int &indx) 
+{ 
+    vis[u] = 1; 
+    Euler[indx++] = u; 
+    for (auto it : adj[u]) { 
+        if (!vis[it]) { 
+            eulerTree(it, indx); 
+            Euler[indx++] = u; 
+        } 
+    } 
+} 
+
+// Function to print Euler Tour of tree 
+void printEulerTour(int root, int N) 
+{ 
+    int index = 0;   
+    eulerTree(root, index); 
+    for (int i = 0; i < (2*N-1); i++) 
+        cout << Euler[i] << " "; 
+} 
+
+// Driver code 
+int main() 
+{ 
+    int N = 4; 
+
+    add_edge(1, 2); 
+    add_edge(2, 3); 
+    add_edge(2, 4); 
+
+    // Consider 1 as root and print 
+    // Euler tour  
+    printEulerTour(1, N); 
+
+    return 0; 
+}