php版的求表達式的真值表-TrueValueTable，真值表邏輯表達式
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<?php
error_reporting(E_ALL & ~E_NOTICE);
$expression=$_GET['TrueTable']; //讀取輸入框數據
if(!empty($_GET['TrueTable'])){
$expression=strtoupper($expression); //將輸入的小寫字母，替代成大寫字母
$expressionArr=str_split($expression); //將$expression轉換成數組
foreach($expressionArr as $v){ //把字母放在 $varTotal數組中
if($v>='A' && $v<='Z'){
$varTotal[]=$v;
}
}
$varTotal = array_unique($varTotal); //去掉$varTotal數組中重復的字母
sort($varTotal); //$varTotal數組中字母正向排序
$varTotal1 = preg_replace("/([A-Z])/","$\\1",$varTotal); //$varTotal1數組中字母變成變量
$maxN = count($varTotal);
//$expressionArr = preg_replace("/([A-Z])/","$\\1",$expressionArr); //$expressionArr數組中字母變成變量
$newExpression=implode('',$expressionArr); //$expressionArr數組變成字符串
//echo $newExpression."<br />";
$newExpression= preg_replace("/([A-Z])->([A-Z])/","!\\1|\\2",$newExpression);
$newExpression= preg_replace("/(\(.*?\))->([A-Z])/","!\\1|\\2",$newExpression);
$newExpression= preg_replace("/(\(.*?\))->(.*?)/","!\\1|\\2",$newExpression);
$newExpression= preg_replace("/([A-Z])->(.*?)/","!\\1|\\2",$newExpression);
$expressionArr=str_split($newExpression); //將$expression轉換成數組
$expressionArr = preg_replace("/([A-Z])/","$\\1",$expressionArr);
$newExpression=implode('',$expressionArr);
//echo $newExpression;
}
?>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>真值表查詢1.0 BY:小臻</title>
</head>
<body>
<span>$_GET['TrueTable'] ?>"/>
<input type="submit" value="確定"/> <br /> <br />
<!--<input type="reset" value="取消" /><br /><br />
<input type="button" value="∨" />
<input type="button" value="∧" />
<input type="button" value="┐" />
<input type="button" value="→" />
<input type="button" value="↔" /><br /><br />-->
</form>
<!--[ 說明：析取(∨) , 合取(∧) , 非(┐) , 蘊含(→) , 等價(↔) ]-->
<p>[ 說明：析取(|) , 合取(&) , 非(!) , 蘊含(->) , 等價(=) ]</p>
<table width="300px">php
echo "<tr>";
if(!empty($_GET['TrueTable'])){
foreach($varTotal as $v){
echo "<td>{$v}</td>";
}
echo "<td>結果</td>";
$result=pow(2,$maxN);
for($i=0;$i<$result;$i++){
$resultN[$i]=sprintf("%0{$maxN}d",decbin($i));
$resultN[$i]=str_split($resultN[$i]);
}
foreach($resultN as $k=>$v){
echo "<tr>";
foreach($resultN[$k] as $k1=>$v1){
echo "<td>".$v1."</td>";
$varTotal2[$k1]=$varTotal1[$k1]."=".$v1;
//echo $varTotal2[$k1]." ";
eval($varTotal2[$k1].";");
}
//echo $newExpression;
eval("\$varTotal3[] = ".$newExpression.";");
foreach($varTotal3 as $k2=>$v){
if($v==NULL){
$varTotal3[$k2]=0;
}
}
echo "<td>".$varTotal3[$k]."</td>";
echo "</tr>";
}
//print_r($varTotal3);
}
?>
</table>
</div>
</body>
</html>
