PHP Exercises: Compute the maximum value of the sum of the passing integers

Last update on December 20 2024 10:18:17 (UTC/GMT +8 hours)

Your task is to develop a small part of spreadsheet software.
Write a PHP program which adds up columns and rows of given table as shown in the following figure:

Pictorial Presentation:

PHP: Compute the maximum value of the sum of the passing integers.

Input: n (the size of row and column of the given table)
1st row of the table
2nd row of the table
:
:
n th row of the table
The input ends with a line consisting of a single 0.

Sample Output:
The maximum value of the sum of integers passing according to the rule on one line.

Sample Solution:

PHP Code:

<?php
// Continuous loop to read input lines until '0' is entered
while (($line = trim(fgets(STDIN))) !== '0') {
    // Convert the input line to an integer representing the size of the square matrix
    $n = (int)$line;

    // Create a 2D array (matrix) filled with zeros, with dimensions ($n + 1) x ($n + 1)
    $arr = array_fill(0, $n + 1, array_fill(0, $n + 1, 0));

    // Loop through each row of the matrix to populate values and calculate row and column sums
    for ($i = 0; $i < $n; $i++) {
        // Read a line from standard input and trim leading/trailing whitespaces
        $line = trim(fgets(STDIN));

        // Iterate through the elements of the current row
        foreach (explode(' ', $line) as $j => $m) {
            // Convert the element to an integer
            $m = (int)$m;

            // Assign the value to the matrix and update row and column sums
            $arr[$i][$j] = $m;
            $arr[$i][$n] += $m;  // Update row sum
            $arr[$n][$j] += $m;  // Update column sum
        }
    }

    // Calculate and assign the sum of all values in the last row and last column
    $arr[$n][$n] = array_sum($arr[$n]);

    // Display a message indicating the table with the sum of rows and columns
    echo "The table with sum of rows and columns:\n";
    
    // Loop through each row and column to print the matrix
    for ($i = 0; $i <= $n; $i++) {
        for ($j = 0; $j <= $n; $j++) {
            // Format and print each matrix element
            printf('%5d', $arr[$i][$j]);
        }
        // Move to the next line after printing a row
        echo PHP_EOL;
    }
}
?>

Explanation:

Loop for Continuous Input:

Continuously reads lines of input until the user enters '0'.

Matrix Size Initialization:

Converts each input line to an integer, $n, which represents the size of an n x n square matrix.

2D Array Initialization:

Creates a 2D array, $arr, initialized to zero with dimensions (n+1) x (n+1).
The extra row and column will store row and column sums.

Matrix Population and Sum Calculation:

Loops through each row of the matrix to populate values.
For each row:

Reads a line of space-separated integers and splits it into an array.
Iterates through each integer, assigns it to the corresponding position in $arr, and updates:

The row sum in the last column ($arr[$i][$n]).
The column sum in the last row ($arr[$n][$j]).

Total Sum Calculation:

The sum of all values in the matrix is stored in the bottom-right corner ($arr[$n][$n]).

Output the Matrix with Sums:

Displays a message: "The table with sum of rows and columns:".
Loops through each element in the matrix to print the matrix in a formatted way.
Each element is printed with a width of 5, aligning values in columns.

Sample Input:
4
25 69 51 26
68 35 29 54
54 57 45 63
61 68 47 59
0

Sample Output:

The table with sum of rows and columns:
   25   69   51   26  171
   68   35   29   54  186
   54   57   45   63  219
   61   68   47   59  235
  208  229  172  202  811

Flowchart:

PHP Code Editor:

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