Simple PHP algorithm questions (with expansion)

Simple PHP algorithm question (to be improved...)

Only print 0

　The specific number is determined by the input parameter n

　If n=5, print 00000

Print n 0s according to the n value

Print a line of 0101010101010101010101

The specific number is determined by the input parameter n

For example, test.php?n=3 prints 010

and prints 010101 according to the n value...

to achieve 1 00 111 0000 1 1111

　for if implementation

<?<span>php

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

</span>?>

for&if statement implementation

　for switch implementation

　while if implementation

　while switch implementation

<?<span>php

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

</span>?>

while&switch statement implementation

Achieve 0 01 010 0101……

Realize 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

Quarterine calculation function that can handle addition, subtraction, multiplication and division

Advanced:

Number of narcissus

Bubble sort method

The above introduces simple PHP algorithm questions (with expansion), including relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.