Merge pull request #27 from neha030/devp1

quick sort added

Author: unnati914

quicksort.cpp

@@ -0,0 +1,50 @@
+#include<bits/stdc++.h>
+using namespace std;
+int partition(int a[],int lb,int ub)
+{
+   int pivot=a[lb];
+   int start=lb;
+   int  end=ub;
+   while(start<end)
+   {
+       while(a[start]<=pivot)
+       {
+           start++;
+       }
+       while(a[end]>pivot)
+       {
+           end--;
+       }
+       if(start<end)
+       swap(a[start],a[end]);
+       
+   }
+   swap(a[lb],a[end]);
+   return end;
+}
+void quicksort(int a[],int lb,int ub)
+{
+    if(lb<ub)
+    {
+        int loc;
+        loc=partition(a,lb,ub);
+        quicksort(a,lb,loc-1);
+        quicksort(a,loc+1,ub);
+
+    }
+}
+void print(int a[], int n)
+{
+    int i;
+    for(i=0;i<n;i++)
+    cout<<a[i]<<" ";
+}
+int main()
+{
+    int a[]={7,6,10,5,9,2,1,15,7};
+    int n=sizeof(a)/sizeof(a[0]);
+    cout<<"After quicksort"<<endl;
+    quicksort(a,0,n-1);
+    print(a,n);
+    return 0;
+}