Submission a69bc672...

ChallengeRemove duplicate elements
Submitterwicketh.eth
Submitted at2018-58-09
Gas used5142364
/**
 * This file is part of the 1st Solidity Gas Golfing Contest.
 *
 * This work is licensed under Creative Commons Attribution ShareAlike 3.0.
 * https://creativecommons.org/licenses/by-sa/3.0/
 */

pragma solidity 0.4.24;

contract Unique {
    function isUnique(uint[] input, uint len, uint value) private pure returns(bool) {
        for(uint i = 0; i < len; i++) {
            if(input[i] == value) return false;
        }
        return true;
    }

    /**
     * @dev Removes all but the first occurrence of each element from a list of
     *      integers, preserving the order of original elements, and returns the list.
     *
     * The input list may be of any length.
     *
     * @param input The list of integers to uniquify.
     * @return The input list, with any duplicate elements removed.
     */
    function uniquify(uint[] input)
        public payable
        returns(uint[] ret) 
    {
        uint ptr = 0;
        for(uint i = 0; i < input.length; i++) {
            if(isUnique(input, i, input[i])) {
                input[ptr++] = input[i];
            }
        }

        ret = new uint[](ptr);
        for(i = 0; i < ret.length; i++) {
            ret[i] = input[i];
        }

        return ret;
    }
}