PHP determines whether the input string is a palindrome

Palindrome: forward and reverse order are exactly the same

<code><span>$string</span>=<span>"abc126321cba"</span>;
  <span>$stra</span>=<span>array</span>();
  <span>$strb</span>=<span>array</span>();
  <span>$res</span>=checkhuiwen(<span>$string</span>);
  <span><span>function</span><span>checkhuiwen</span><span>(<span>$string</span>)</span>{</span><span>//输入字符串转换为数组</span><span>for</span>(<span>$i</span>=<span>0</span>;<span>$i</span><strlen(<span>$string</span>);<span>$i</span>++){
        <span>$stra</span>[<span>$i</span>]=<span>$string</span>[<span>$i</span>];
      }
       <span>//逆序输出数组array_reverse</span><span>$strb</span>=array_reverse(<span>$stra</span>);
       <span>//判断两数组是否相等，相等为回文</span><span>for</span>(<span>$i</span>=<span>0</span>;<span>$i</span><count(<span>$stra</span>);<span>$i</span>++){
       <span>if</span>(<span>$stra</span>[<span>$i</span>]!=<span>$strb</span>[<span>$i</span>]){
          <span>return</span><span>1</span>;
          <span>break</span>;
       }     
  }
  <span>return</span><span>2</span>;
  }
  <span>if</span>(<span>$res</span>==<span>2</span>){
    <span>echo</span><span>"YES"</span>;
  }<span>else</span>{
    <span>echo</span><span>"NO!"</span>;
  }</code>

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