当使用左移和大整数时我会得到不同的结果，当我使用硬编码时，为什么会这样，如何克服？
BigInteger num = 1779033703;
BigInteger result = num << 30;
Console.WriteLine(result);
Console.WriteLine(1779033703 << 30);
结果
1910222893216694272
-1073741824
答案 0 :(得分：2)
因为常规<?php
include('includes/sessions.php');
include('includes/db_connection.php');
include('includes/functions.php');
include('includes/header.php');
include('includes/navbar-logged.php');
?>
<?php
$crawlId = isset($_GET['urlId']) ? $_GET['urlId'] : '';
?>
<?php
if (!isset($_GET['page'])) {
$page = 1;
} else {
$page = $_GET['page'];
}
$userInfo = get_logged_in_users_details($member);
$canEdit = false;
if ($userInfo['user_class'] === 'Site Administrator') {
$canEdit = true;
}
$sort = isset($_GET['sort']) ? $_GET['sort'] : 'domain_id';
$max_results = 500;
$from = ($page * $max_results) - $max_results;
if (isset($crawlId)) {
$rows = DB::getInstance()->select("
SELECT *
FROM `domains`
WHERE `domain_available`='Y' AND `domain_crawler_id`='{$crawlId}'
ORDER BY `{$sort}` DESC
LIMIT :from, :max_results",
[
'from' => [
'type' => PDO::PARAM_INT,
'value' => $from
],
'max_results' => [
'type' => PDO::PARAM_INT,
'value' => $max_results
]
]);
} else {
$rows = DB::getInstance()->select("
SELECT *
FROM `domains`
WHERE `domain_available`='Y' AND `domain_category`!='N/A' AND `domain_crawler_id`='0'
ORDER BY `{$sort}` DESC
LIMIT :from, :max_results",
[
'from' => [
'type' => PDO::PARAM_INT,
'value' => $from
],
'max_results' => [
'type' => PDO::PARAM_INT,
'value' => $max_results
]
]);
}
if (isset($crawlId)) {
$total_results = DB::getInstance()->selectValue("SELECT count(*) FROM `domains` WHERE`domain_crawler_id`='{$crawlId}'");
} else {
$total_results = DB::getInstance()->selectValue("SELECT count(*) FROM `domains` WHERE `domain_available`='Y' AND `domain_category`!='N/A' AND `domain_crawler_id`='0'");
}
echo $total_results;
if (count($rows) < 1) {
stderr('Sorry, <b>no</b> domains to show you yet!');
}
$backLinksData = getBackLinksByDomains($rows);
$isPremiumUser = (int)$user['paid_fees'] === 1;
?>
<div class="panel panel-primary">
<div class="panel-heading">Search for expired domains quickly.</div>
<div class="panel-body">
<form action="results.php" method="get" class="form-horizontal container-fluid" role="form">
<div class="row form-group">
<div class="col-sm-6 text-right">
<label for="" class="control-label">Domain Contains:</label>
</div>
<div class="col-sm-6">
<input type="text" name="keywords" class="form-control" size="40" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label for="" class="control-label">Anchor Contains:</label>
</div>
<div class="col-sm-6">
<input type="text" name="anchor" class="form-control" size="40" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label">DA:</label>
</div>
<div class="col-sm-6">
<input type="number" min="0" max="100" name="da" value="0" class="form-control" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label">PA:</label>
</div>
<div class="col-sm-6">
<input type="number" min="0" max="100" name="pa" value="0" class="form-control" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label">TF:</label>
</div>
<div class="col-sm-6">
<input type="number" min="0" max="100" name="tf" value="0" class="form-control" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label">CF:</label>
</div>
<div class="col-sm-6">
<input type="number" min="0" max="100" name="cf" value="0" class="form-control" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label">Domains Born After:</label>
</div>
<div class="col-sm-6">
<input type="number" min="1990" max="2016" name="age" value="1999" class="form-control" />
</div>
</div>
<div class="row form-group">
<div class="col-sm-6 text-right">
<label class="control-label" style="display: inline-block;"> </label>
</div>
<div class="col-sm-6 text-right">
<button type="submit" name="submit" class="btn btn-default">Search</button>
</div>
</div>
</form>
</div>
<div class="panel-footer">Search for domains using <b>your</b> criteria.</div>
</div>
<div class="panel panel-primary">
<div class="panel-heading">Browse Domains - <b>*<font color="orange">spam</font>*</b> = Potential spam domain! <b>*<font color="red">HP</font>*</b> = A homepage link points to this domain!</div>
<div class="panel-body">
<table class="table table-striped table-condensed table-hover table-responsive">
<thead>
<tr>
<th>Alexa</th>
<th>Domain / Category</th>
<th><a href="expired-domains.php?sort=domain_moz_da">DA</a></th>
<th><a href="expired-domains.php?sort=domain_moz_pa">PA</a></th>
<th><a href="expired-domains.php?sort=domain_tf">TF</a></th>
<th><a href="expired-domains.php?sort=domain_cf">CF</a></th>
<th><a href="expired-domains.php?sort=domain_indexed">Indexed</a></th>
<th><a href="expired-domains.php?sort=domain_age">Age</a></th>
<th>BL</th>
<th><a href="expired-domains.php?sort=domain_ref_domains">RD</a></th>
<th>Found</th>
<?php if ($canEdit): ?>
<th>Actions</th>
<?php endif; ?>
</tr>
</thead>
<tbody>
<?php foreach ($rows as $row) { ?>
<?php
//$bgcolor = ($bgcolor == '#eeeeee'? '#ffffff': '#eeeeee');
$domID = $row['domain_id'];
$domNM = $row['domain_name'];
$domDT = $row['domain_date'];
$domAL = $row['domain_alexa_rank'];
$domDA = $row['domain_moz_da'];
$domPA = $row['domain_moz_pa'];
$domTF = $row['domain_tf'];
$domCF = $row['domain_cf'];
$domRD = $row['domain_ref_domains'];
$domDC = $row['domain_age'];
$domIN = $row['domain_indexed'];
$domHP = $row['domain_homepage'];
$domCT = $row['domain_category'];
$time_1 = date('Y-m-d H:i:s', strtotime($domDT . ' +1 hour'));
$time_2 = date('Y-m-d H:i:s', time());
$string = $domNM;
$array = array("sunglasses","payday","casino","viagra","cashloans","loans","sex","porn","xxx");
$spam = 0;
foreach ($array as $token) {
if (stristr($string, $token) !== FALSE) {
$spam = 1;
}
}
?>
<tr>
<td><?php echo htmlspecialchars($domAL); ?></td>
<td>
<?php
$domainUrl = $isPremiumUser ? $domNM : getObscuredUrl($domNM);
$domainCat = ($domCT == "N/A") ? "<font color=\"red\"><b>Uncategorized</b></font>" : "<font color=\"green\"><b>{$domCT}</b></font>";
?>
<a href="domain-details.php?id=<?php echo $domID; ?>"><b><?php echo htmlspecialchars($domainUrl); ?></b></a> <b>in</b> <?php echo $domainCat; ?>
<?php if ($time_2 <= $time_1) { ?>
<b>(<font color="red">NEW</font>)</b>
<?php } ?>
<?php if ($spam) { ?>
<b>*<font color="orange">spam</font>*</b>
<?php } ?>
<?php if ($domHP) { ?>
<b>*<font color="red">HP</font>*</b>
<?php } ?>
</td>
<td>
<?php echo $domDA; ?>
</td>
<td>
<?php echo $domPA; ?>
</td>
<td>
<?php echo $domTF; ?>
</td>
<td>
<?php echo $domCF; ?>
</td>
<td>
G=<?php if ($domIN == 0) { echo "<font color=\"red\"><b>No</b></font>"; } else { echo "<font color=\"green\"><b>Yes</b></font>"; } ?>
</td>
<td>
<?php if ($domDC == "????") { echo "<b><font color=\"red\">????</font></b>"; } else { echo $domDC; } ?>
</td>
<td>
<?= isset($backLinksData[$domNM]) ? $backLinksData[$domNM] : 0; ?>
</td>
<td>
<?php if (empty($domRD)) { echo "-"; } else { echo $domRD; } ?>
</td>
<td>
<b><?php echo date("m.d.y", strtotime($domDT)); ?></b>
</td>
<?php if ($canEdit): ?>
<td>(<a href="master-edit-domain.php?id=<?php echo $domID ?>">e</a>)-(<a href="master-delete-domain.php?id=<?php echo $domID ?>" onclick="return confirm('Are you sure you want to delete this domain?');">d</a>)</td>
<?php endif; ?>
</tr>
<?php } ?>
</tbody>
</table>
</div>
<div class="panel-footer text-center">
<?php pagination($page, $total_results, $max_results) ?>
</div>
</div>
<?php
include('includes/footer.php');
上的1779033703 << 30（32位有符号整数），您正在遇到溢出，因此它再次从int开始。 int.MinValue可以处理更大的值，因此不会受到溢出的影响。
尝试使用BigInteger（64位有符号整数），您将看到与long相同的结果。