In this article we will learn about some of the frequently asked C++ programming questions in technical like “binary search in c++” Code Answer’s. If you’re new to coding, you probably have lots of them. Errors are sometimes obvious, such as a simple syntax error or incorrect variable name, and sometimes they are difficult to understand, with only a cryptic code to guide you. Below are some solution about “binary search in c++” Code Answer’s.
how to do binary search in c++ using STL
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// BY shivam kumar KIIT
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#include<bits/stdc++.h>
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usind namespace std;
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int main()
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{
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int arr[]={10,2,34,2,5,4,1};
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sort(arr,arr+7);//sort array in ascending order before using binary search
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binary_search(arr,arr+7,10);//return 1 as element is found
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binary_search(arr,arr+7,3);//return 0 as element is not found
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return 0;
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}
binary search function in c++
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#include<iostream>
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using namespace std;
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int binarySearch(int arr[], int p, int r, int num) {
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if (p <= r) {
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int mid = (p + r)/2;
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if (arr[mid] == num)
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return mid ;
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if (arr[mid] > num)
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return binarySearch(arr, p, mid-1, num);
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if (arr[mid] > num)
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return binarySearch(arr, mid+1, r, num);
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}
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return -1;
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}
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int main(void) {
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int arr[] = {1, 3, 7, 15, 18, 20, 25, 33, 36, 40};
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int n = sizeof(arr)/ sizeof(arr[0]);
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int num = 33;
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int index = binarySearch (arr, 0, n-1, num);
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if(index == -1)
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cout<< num <<" is not present in the array";
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else
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cout<< num <<" is present at index "<< index <<" in the array";
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return 0;
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}
binary search in c++
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#include<iostream>
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using namespace std;
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int binarySearch(int arr[], int p, int r, int num) {
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if (p <= r) {
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int mid = (p + r)/2;
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if (arr[mid] == num)
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return mid ;
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if (arr[mid] > num)
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return binarySearch(arr, p, mid-1, num);
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if (arr[mid] < num)
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return binarySearch(arr, mid+1, r, num);
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}
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return -1;
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}
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int main(void) {
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int arr[] = {1, 3, 7, 15, 18, 20, 25, 33, 36, 40};
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int n = sizeof(arr)/ sizeof(arr[0]);
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int num = 33;
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int index = binarySearch (arr, 0, n-1, num);
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if(index == -1)
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cout<< num <<" is not present in the array";
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else
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cout<< num <<" is present at index "<< index <<" in the array";
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return 0;
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}
Binary search in c++
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//By Sudhanshu Sharan
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#include<iostream>
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#include<cmath>
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using namespace std;
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// BCT= o(1) and WCT=O(logn) time taken for unsucessful search is always o(logn)
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int BinSearch( int arr[],int key,int len)
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{
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int h,mid,l;
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l=0;
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h=len-1;
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while(l<=h)
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{
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mid=((l+h)/2);
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if(key==arr[mid])
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return mid;
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else if(key<arr[mid])
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h=mid-1;
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else
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l=mid+1;
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}
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return -1;
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}
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int main()
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{
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int key,i,len;
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int arr[] = {1,2,3,6,9,12,15,34,54};
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len=sizeof(arr)/sizeof(arr[0]);
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cout<<"enter the key to be searched";
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cin>>key;
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int result= BinSearch(arr,key,len);
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(result == -1)
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? cout<<"Element is not present in the array"<<endl
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: cout<<"Element is present at index : "<<result<<endl;
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for(i=0;i<len-1;i++)
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cout<<arr[i]<<" ";
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return 0;
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}
Binary search in c++
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//By Sudhanshu Sharan
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#include<iostream>
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#include<cmath>
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using namespace std;
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// BCT= o(1) and WCT=O(logn) time taken for unsucessful search is always o(logn)
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int BinSearch( int arr[],int key,int len)
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{
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int h,mid,l;
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l=0;
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h=len-1;
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while(l<=h)
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{
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mid=((l+h)/2);
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if(key==arr[mid])
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return mid;
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else if(key<arr[mid])
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h=mid-1;
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else
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l=mid+1;
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}
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return -1;
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}
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int main()
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{
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int key,i,len;
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int arr[] = {1,2,3,6,9,12,15,34,54};
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len=sizeof(arr)/sizeof(arr[0]);
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cout<<"enter the key to be searched";
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cin>>key;
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int result= BinSearch(arr,key,len);
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(result == -1)
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? cout<<"Element is not present in the array"<<endl
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: cout<<"Element is present at index : "<<result<<endl;
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for(i=0;i<len-1;i++)
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cout<<arr[i]<<" ";
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return 0;
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}
c++ binary search
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int result = -1;
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int low = 0;
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int high = N-1; // N - # of elements
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while (low <= high)
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{ mid = (low + high) / 2;
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if ( item == vector[mid])
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{ result = mid;
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break;
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}
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else if (item > vector[mid] )
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{ low = mid + 1; }
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else { high = mid - 1; }
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}
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