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implementation of binary search

my code for binary search is not working....where i am wrong....here my code goes :

#include<bits/stdc++.h>
using namespace std;
int BS(int[],int,int,int);
int main()
{
 int n;
 scanf("%d",&n);
 int a[n],i;
 for(i=0;i<n;i++)
 {
  scanf("%d",&a[i]);
 }
 sort(a,a+n);
 int t;
 scanf("%d",&t);
 while(t--)
  {
  int numberToSearch;
  scanf("%d",&numberToSearch);
   int r;
   r = BS(a,0,n-1,numberToSearch);
   printf("%d\n",r);
     }
return 0; 
}
int BS(int x[],int f,int l,int test)
{
 int mid;
 while(f<=l)
 { 
 mid=(l-f)/2+f;
 if(x[mid]==test)
 {
  return (mid);
 }
 else if(x[mid]<test)
 {
  l=mid+1;
 }
 else
 {
  f=mid-1;
 }
    }
 return (-1);
}

Asked by: Abhishek_Chaudhary on April 7, 2019, 1:04 p.m. Last updated on April 7, 2019, 1:04 p.m.


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1 Answer(s)

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You should better check the values you are assigning to the lowerbound and upperbound of your binary search.

Gyanesha_Prajjwal last updated on April 7, 2019, 1:04 p.m. 0    Reply    Upvote   

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