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<?php $cups = array(); for($i=0; $i<100; $i++){ $cups[$i] = 0; } for($x=1; $x<100; $x++){ for($y=$x; $y<100; $y+=$x){ $cups[$y] = !$cups[$y]; } } $selected = array(); foreach($cups as $key => $value){ if($value == 1){ $selected[] = $key; } } $sel_str = implode(', ', $selected); echo $sel_str; echo "\n\n\n\n"; foreach ($selected as $num) { settype($num, 'integer'); echo decbin($num)."\n"; } echo "\n\n\n\n"; print_r($cups);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
1, 4, 9, 16, 25, 36, 49, 64, 81 1 100 1001 10000 11001 100100 110001 1000000 1010001 Array ( [0] => 0 [1] => 1 [2] => [3] => [4] => 1 [5] => [6] => [7] => [8] => [9] => 1 [10] => [11] => [12] => [13] => [14] => [15] => [16] => 1 [17] => [18] => [19] => [20] => [21] => [22] => [23] => [24] => [25] => 1 [26] => [27] => [28] => [29] => [30] => [31] => [32] => [33] => [34] => [35] => [36] => 1 [37] => [38] => [39] => [40] => [41] => [42] => [43] => [44] => [45] => [46] => [47] => [48] => [49] => 1 [50] => [51] => [52] => [53] => [54] => [55] => [56] => [57] => [58] => [59] => [60] => [61] => [62] => [63] => [64] => 1 [65] => [66] => [67] => [68] => [69] => [70] => [71] => [72] => [73] => [74] => [75] => [76] => [77] => [78] => [79] => [80] => [81] => 1 [82] => [83] => [84] => [85] => [86] => [87] => [88] => [89] => [90] => [91] => [92] => [93] => [94] => [95] => [96] => [97] => [98] => [99] => )

preferences:
266.64 ms | 409 KiB | 375 Q