Longest Common Prefix Matching | Set | A Utility Function to find the common prefix between first and last strings ; Compare str1 and str2 ; A Function that returns the longest common prefix from the array of strings ; sorts the N set of strings ; prints the common prefix of the first and the last String of the set of strings ; Driver Code
function commonPrefixUtil ( str1 , str2 ) { let result = " " ; let n1 = str1 . length , n2 = str2 . length ; for ( let i = 0 , j = 0 ; i <= n1 - 1 && j <= n2 - 1 ; i ++ , j ++ ) { if ( str1 [ i ] != str2 [ j ] ) { break ; } result += str1 [ i ] ; } return ( result ) ; } function commonPrefix ( arr , n ) { arr . sort ( ) ; document . write ( commonPrefixUtil ( arr [ 0 ] , arr [ n - 1 ] ) + " " ) ; } let arr = [ " " , " " , " " , " " ] ; let n = arr . length ; commonPrefix ( arr , n ) ;