只打印0
具体个数由输入的参数n决定
如n=5就打印00000
<?php $n = $_GET['n']; for ($i=0; $i < $n; $i++) { echo "0"; } ?>
打印一行 0101010101010101010101
具体个数由输入的参数n决定
如test.php?n=3打印010
<?php $n = $_GET['n']; for ($i=0; $i < $n; $i++) { if ($i % 2 ==0) { echo "0"; } else{ echo "1"; } } ?>
实现1 00 111 0000 11111
for if 实现
<?php for ($i = 0; $i < 10; $i++) { for ($j = 0; $j <= $i; $j++) { if ($i % 2 == 0) { echo '0'; } else { echo '1'; } } echo '<br/>'; } ?>
for switch 实现
<?php for ($i = 0; $i < 10; $i++) { for ($j = 0; $j <= $i; $j++) { switch ($j % 2) { case '0': echo "0"; break; case '1': echo "1"; break; } } echo '<br/>'; } ?>
while if 实现
while switch 实现
<?php $i = 0; while ($i < 10) { $j = 0; while ($j <= $i) { switch ($i % 2) { case 0: echo '0'; break; case 1: echo '1'; break; } $j++; } echo '<br/>'; $i++; } ?>
实现0 01 010 0101……
实现0 01 012 0123 3210 210 10 0
做个计算器
如test.php?a=1&b=2&operator=jia输出3
如test.php?a=5&b=2&operator=jian输出3
如test.php?a=2&b=5&operator=cheng输出10
如test.php?a=6&b=3&operator=chu输出2
<?php $a = $_GET['a']; $b = $_GET['b']; $operator = $_GET['operator']; function calculate($a,$b,$operator) { switch ($operator) { case 'jia': $result = $a + $b; return $result; break; case 'jian': $result = $a - $b; return $result; break; case 'cheng': $result = $a * $b; return $result; break; case 'chu': $result = $a / $b; return $result; break; } } echo calculate($a,$b,$operator); ?>
以上所述就是本文的全部内容了,希望大家能够喜欢。

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