binary.cpp

#include <iostream>
using namespace std;

int a[6]={20,5,1,3,17,3};
bool binarySearch(int first, int last, int key);
int main(){
int key;

    cout<<"Enter the item to search"<<endl;
    cin>>key;
    bool found=false;
    found=binarySearch(0,5,key);
    if(found){
    cout<<key<<"is found"<<endl;
    }else{
        cout<<key<<"not found"<<endl;
    }
}
  bool binarySearch(int first, int last, int key){
      int index = -1;
if (first > last)
return false;
else {
index = (first + last)/2;
if (key == a[index])
return true;
else if (key < a[index])
return binarySearch(first, index -1, key);
else
return binarySearch(index + 1, last, key);
} //end else
  }