How to Use php for multiplication, how to buy a chicken for a hundred dollars, and how to bridge the bridge

How to Use php for multiplication, how to buy a chicken for a hundred dollars, and how to bridge the bridge
Exercise Question 1: crossing the bridge

Suppose someone has 100,000 in cash.

Each time you pass through an intersection, you need to pay a fee.

The payment rule is that when his cash is greater than 50,000, he must pay 5% each time. If his cash is less than or equal to 50,000, he must pay 5,000 each time.

Please write a program to calculate how many times this person can pass through this intersection.

for ($i=100000,$num = 0; $i >= 5000; ) {     if ($i >= 50000) {        $i = 0.95*$i;    }else{        $i = $i -5000;    }    $num = $num + 1;}echo $num,'<br />';

Exercise Question 2: Multiplication

for ($i=1; $i <= 9 ; $i++) {     for($j=1; $j<=$i; $j++) {        echo $j,'*',$i ,'=' , $j*$i , '&nbsp;';    }    echo '<br />';}

Exercise 3: buy a chicken for a hundred dollars

Course 22 Zhang qiujian computing Sutra was written in the 5th century. The author is from Northern Wei.

The last question in the book is a bright spot. It is also known as the question of "buy a chicken for a hundred dollars,

The original texts in the famous saying that the county magistrate asked the prodigy are as follows:

Today there is a rooster, worth five; a rooster, worth three; a rooster, worth one;

I want to buy more than one chicken for a hundred dollars. What are the geometric aspects of the rooster, the mother, and the chicks?

The question is: the rooster has five yuan, the hen has three yuan, and the chicken has three yuan,

Now I have bought 100 chickens for 100 RMB,

Q: How many of the 100 chickens are rooster, hen, and chicken? (Set at least one for each type)

for ($i=1; $i <100 ; $i++) {     for ($j=1; $j < 100; $j++) {         for ($k=1; $k <100 ; $k++) {             if ( ($i+$j+$k == 100)&&($i*5+$j*3+$k/3 == 100) ) {                echo $i,'<br />',$j,'<br />',$k,'<br />';            }        }    }}