PHP Exercises: Compute and print sum of two given integers

Last update on May 30 2022 11:48:29 (UTC/GMT +8 hours)

PHP: Exercise-54 with Solution

Write a PHP program to compute and print sum of two given integers (more than or equal to zero). If given integers or the sum have more than 80 digits, print "overflow".

Pictorial Presentation:

PHP: Compute and print sum of two given integers.

Sample Solution: -

PHP Code:

<?php
fscanf(STDIN, '%d', $N);
for ($i = 0; $i < $N; $i++) {
    fscanf(STDIN, '%s', $a);
    fscanf(STDIN, '%s', $b);
    if (max(strlen($a), strlen($b)) > 80) {
        echo "overflow\n";
        continue;
    }
    $arr = array_fill(0, 81, 0);
    $a = sprintf('%081s', $a);
    $b = sprintf('%081s', $b);
    for ($j = 80; $j > 0; $j--) {
        $n = $arr[$j] + $a[$j] + $b[$j];
        if ($n >= 10) {
            $arr[$j] = substr($n, 1);
            $arr[$j - 1] += 1;
        } else {
            $arr[$j] = $n;
        }
    }
    $result = preg_replace('/^0+(\d+)$/', '$1', implode('', $arr));
    if (strlen($result) > 80) {
        echo "overflow\n";
    } else {
        echo $result, PHP_EOL;
    }
}
?>

Sample Output:

46
overflow
overflow
overflow
overflow
...
overflow
overflow
overflow

Flowchart:

PHP Code Editor:

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Previous: Write a PHP program to compute the radius and the central coordinate (x, y) of a circle which is constructed by three given points on the plane surface.
Next: Write a PHP program that accepts six numbers as input and sorts them in descending order.

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PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC