PHP algorithm example sharing

Only print 0

　The specific number is determined by the input parameter n

　If n=5, print 00000

 $n = $_GET['n'];
 for ($i=0; $i < $n; $i++) {
 echo "0";
 }
? >

Print a line 0101010101010101010101

　The specific number is determined by the input parameter n

　For example test.php?n=3 print 010

 $n = $_GET['n'];
 for ($i=0; $i < $n; $i++) {
 if ($i % 2 ==0 ) {
 echo "0";
 } else{
 echo "1";
 }
 }
?>

Achieve 1 00 111 0000 11111

　for if implementation

for ($i = 0; $i < 10; $i++) {
 for ($j = 0; $j <= $i; $j++) {
 if ($i % 2 == 0) {
 echo '0';
 } else {
 echo '1';
 }
 }
 echo '';
}

?>

　For switch implementation

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 ' ';
}

?>

　while if implementation

　while switch implementation

$i = 0;
while ($i < 10) {
 $j = 0;
 while ($j <= $i) {
 switch ($i % 2) {
 case 0:
 echo '0';
 break;
 case 1:
 echo '1';
 break;
 }
 $j++;
 }
 echo '';
 $ i++;
}

?>

Achieve 0 01 010 0101……

Achieve 0 01 012 0123 3210 210 10 0

Make a calculator

　For example, test.php?a=1&b=2&operator=jia outputs 3

　For example, test.php?a=5&b=2&operator=jian outputs 3

　For example, test.php?a=2&b=5&operator=cheng outputs 10

　For example, test.php?a=6&b=3&operator=chu outputs 2

 $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);
?>

The above is the entire content of this article, I hope you all like it.

php