Number of subarrays have bitwise OR >= K | C ++ implementation of the approach ; Function to build the segment tree ; Function to return the bitwise OR of segment [ L . . R ] ; Function to return the count of required sub - arrays ; Build segment tree ; Query segment tree for bitwise OR of sub - array [ i . . j ] ; Driver code
#include <bits/stdc++.h> NEW_LINE using namespace std ; #define N  100002 NEW_LINE int tree [ 4 * N ] ; void build ( int * arr , int node , int start , int end ) { if ( start == end ) { tree [ node ] = arr [ start ] ; return ; } int mid = ( start + end ) >> 1 ; build ( arr , 2 * node , start , mid ) ; build ( arr , 2 * node + 1 , mid + 1 , end ) ; tree [ node ] = tree [ 2 * node ] | tree [ 2 * node + 1 ] ; } int query ( int node , int start , int end , int l , int r ) { if ( start > end start > r end < l ) { return 0 ; } if ( start >= l && end <= r ) { return tree [ node ] ; } int mid = ( start + end ) >> 1 ; int q1 = query ( 2 * node , start , mid , l , r ) ; int q2 = query ( 2 * node + 1 , mid + 1 , end , l , r ) ; return q1 | q2 ; } int countSubArrays ( int arr [ ] , int n , int K ) { build ( arr , 1 , 0 , n - 1 ) ; int count = 0 ; for ( int i = 0 ; i < n ; i ++ ) { for ( int j = i ; j < n ; j ++ ) { int bitwise_or = query ( 1 , 0 , n - 1 , i , j ) ; if ( bitwise_or >= K ) count ++ ; } } return count ; } int main ( ) { int arr [ ] = { 3 , 4 , 5 } ; int n = sizeof ( arr ) / sizeof ( arr [ 0 ] ) ; int k = 6 ; cout << countSubArrays ( arr , n , k ) ; return 0 ; }