<?php
# 1200. Minimum Absolute Difference

# Failed
class Solution {

    /**
     * @param Integer[] $arr
     * @return Integer[][]
     */
    function minimumAbsDifference($arr) {
        $abs_arr = array_map('abs', $arr);
        asort($abs_arr);
        $abs_arr_keys = array_keys($abs_arr);

        $matchs = [];

        $min_diff = 99999999999;

        $limit = count($abs_arr) - 1;
        $f = current($abs_arr);
        for ( $i = 0; $i < $limit; ++$i) {
            $s = next($abs_arr);
            $diff = $s - $f;
            $f = $s;

            $fo = $arr[$abs_arr_keys[$i]];
            $so = $arr[$abs_arr_keys[$i+1]];
            if ( $fo >= $so ) { continue; }

            if ( $diff < $min_diff ) { $min_diff = $diff; }
            if ( ! array_key_exists($diff, $matchs) ) {
                $matchs[$diff] = [[$i, $i+1]]; continue;
            }
            array_push($matchs[$diff], [$i, $i+1]);
        }

        $res = [];

        foreach ( $matchs[$min_diff] as $t ) {
            $f = $arr[$abs_arr_keys[$t[0]]];
            $s = $arr[$abs_arr_keys[$t[1]]];
            array_push($res, [$f, $s]);
        }

        return $res;
    }
}

function main() {
    function r($a, $exp) {
        $S = new Solution;
        $r = $S->minimumAbsDifference($a);
        $str_a   = json_encode($a);
        $str_r   = json_encode($r);
        $str_exp = json_encode($exp);
        echo "Solution().minimumAbsDifference(\"$str_a\") = $str_r | exp: $str_exp\n";
    }
    r([4,2,1,3], [[1,2],[2,3],[3,4]]);
    r([1,3,6,10,15], [[1,3]]);
    r([3,8,-10,23,19,-4,-14,27], [[-14,-10],[19,23],[23,27]]);
}

main();