1.通过for循环将数组中值求和、求平均值
<?php
$num=[1,2,3,4,5,6,7,8,9];
$sum = 0;
for ($i=0,$n=count($num); $i < $n ; $i++) {
$sum += $num[$i];
}
echo '和是: ' .$sum,'<br>';
echo '平均值: '.number_format($sum/count($num),1);
?>
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2.数组翻转
<?php
$stu=['wang','li','zhang','sun','jiang','liu','xu'];
for ($i=0, $j=count($stu)-1; $i < $j; $i++, $j--) {
[$stu[$i],$stu[$j]] = [$stu[$j],$stu[$i]];
}
print_r($stu);
?>
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3.遍历二维数组
<?php
$stu=[
[1,2,3,4],
['a', 'b', 'c', 'd']
];
for ($i=0; $i < count($stu); $i++) {
for ($j=0; $j < count($stu[$i]); $j++) {
echo $stu[$i][$j],' ';
}
}
?>
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4.打印水仙花数
<?php
for ($i=100; $i <= 999; $i++) {
$a = (int)($i/100);
$b = (int)(($i%100)/10);
$c = $i % 10;
if ($i == pow($a,3) + pow($b,3) + pow($c,3)) {
echo $i,'<br>';
}
}
?>
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5.打印100以内的斐波那契数(迭代法)
<?php
$num1 = 1;
$num2 = 1;
echo $num1,' ',$num2,' ';
while (true) {
$num3 = $num1 + $num2;
if ($num3 > 100) {
break;
}
echo $num3,' ';
$num1 = $num2;
$num2 = $num3;
}
?>