php输出空心菱形 php7 php环境搭建 php从入门到精通

<code><span>$a</span>=<span>5</span>;<span>/*控制循环行数*/</span><span>for</span>(<span>$i</span>=<span>1</span>;<span>$i</span>$a;<span>$i</span>++){ 
        <span>for</span>(<span>$b</span>=<span>1</span>;<span>$b</span>$a-<span>$i</span>;<span>$b</span>++){
            <span>echo</span><span>" "</span>;  
        }  
        <span>for</span>(<span>$c</span>=<span>1</span>;<span>$c</span>$i-<span>1</span>)*<span>2</span>+<span>1</span>;<span>$c</span>++){
            <span>if</span>(<span>$c</span>==<span>1</span>||<span>$c</span>==(<span>$i</span>-<span>1</span>)*<span>2</span>+<span>1</span>){
                <span>echo</span><span>"*"</span>;  
            }<span>else</span>{  
                <span>echo</span><span>" "</span>;  
            }  
        }
        <span>echo</span><span>"<br>"</span>;  
    }   
    <span>for</span>(<span>$i</span>=<span>$a</span>-<span>1</span>;<span>$i</span>>=<span>1</span>;<span>$i</span>--){ 
        <span>for</span>(<span>$b</span>=<span>1</span>;<span>$b</span>$a-<span>$i</span>;<span>$b</span>++){
            <span>echo</span><span>" "</span>;  
        } 
        <span>for</span>(<span>$c</span>=<span>1</span>;<span>$c</span>$i-<span>1</span>)*<span>2</span>+<span>1</span>;<span>$c</span>++){
            <span>if</span>(<span>$c</span>==<span>1</span>||<span>$c</span>==(<span>$i</span>-<span>1</span>)*<span>2</span>+<span>1</span>){
                <span>echo</span><span>"*"</span>;  
            }<span>else</span>{  
                <span>echo</span><span>" "</span>;  
            } 
        } 
        <span>echo</span><span>"<br>"</span>;  
    }</code>