Search an element in a sorted and rotated array with duplicates | Function to return the index of the key in arr [ l . . h ] if the key is present otherwise return - 1 ; The tricky case , just update left and right ; If arr [ l ... mid ] is sorted ; As this subarray is sorted , we can quickly check if key lies in any of the halves ; If key does not lie in the first half subarray then divide the other half into two subarrays such that we can quickly check if key lies in the other half ; If arr [ l . . mid ] first subarray is not sorted then arr [ mid ... h ] must be sorted subarray ; Driver code
function search ( arr , l , h , key ) { if ( l > h ) return - 1 ; let mid = parseInt ( ( l + h ) / 2 , 10 ) ; if ( arr [ mid ] == key ) return mid ; if ( ( arr [ l ] == arr [ mid ] ) && ( arr [ h ] == arr [ mid ] ) ) { ++ l ; -- h ; return search ( arr , l , h , key ) } if ( arr [ l ] <= arr [ mid ] ) { if ( key >= arr [ l ] && key <= arr [ mid ] ) return search ( arr , l , mid - 1 , key ) ; return search ( arr , mid + 1 , h , key ) ; } if ( key >= arr [ mid ] && key <= arr [ h ] ) return search ( arr , mid + 1 , h , key ) ; return search ( arr , l , mid - 1 , key ) ; } let arr = [ 3 , 3 , 1 , 2 , 3 , 3 ] ; let n = arr . length ; let key = 3 ; document . write ( search ( arr , 0 , n - 1 , key ) ) ;