Merge pull request #26 from arpit3018/master

Added SegmentTree.cpp

Common Algorithms/segmentTree.cpp

@@ -0,0 +1,40 @@
+#include<iostream>
+#define max_in 1048575
+using namespace std;
+
+void constructTree(int inp[],int segTree[],int low, int high, int pos)
+{
+    if(high == low)
+    {
+        segTree[pos] = inp[low];
+        return;
+    }
+    int mid = (low + high)/2;
+    constructTree(inp,segTree,low,mid,2*pos+1);
+    constructTree(inp,segTree,mid+1,high,2*pos+2);
+    segTree[pos] = segTree[2*pos+1] & segTree[2*pos+2];
+}
+
+int minQuery(int segTree[],int qlow, int qhigh, int low, int high, int pos)
+{
+    if(qlow <= low && qhigh >= high ) //total overlap
+    return segTree[pos];
+    if(qlow > low || qhigh < high)
+    return max_in;
+    int mid = (low + high)/2;
+    return(minQuery(segTree,qlow,qhigh,low,mid,2*pos+1) & minQuery(segTree,qlow,qhigh,mid+1,high,2*pos+2));
+}
+
+int main()
+{
+    int n = 3;
+    int a[] = {1,2,3};
+    int seg[7];
+    for(int i=0;i<7;i++)
+    seg[i] = max_in;
+
+    constructTree(a,seg,0,n-1,0);
+    cout<<minQuery(seg,1,3,0,n-1,0);
+    for(int i=0;i<7;i++)
+    cout<<seg[i]<<endl;
+}