# Robson ▸ Little Red Book ▸ Random sequence

## Chapter 7 - Question 10

Design a program to produce a randomly selected permutation of the integers 1 to 5 such that each appears once and once only.

### Solution 1

`<?` `    // first, declare the numbers in an array` `    \$numbers = array(1, 2, 3, 4, 5);` `    // randomly change the order` `    shuffle(\$numbers);` `    // output the sequence` `    echo implode(', ', \$numbers);` `?>`

Which produces:

1, 3, 5, 2, 4

### Solution 2

This type of script could be used to generate random lottery numbers.

`<?` `    // how many numbers are needed` `    define(HIGHEST, 49);` `    // the amount of numbers to generate` `    define(GENERATE, 6);` `    // start the array` `    \$numbers = array();` `    // add each number to the array` `    for (\$n = 1; \$n <= HIGHEST; \$n++)` `        // add that number` `        \$numbers[] = \$n;        ` `    // randomly change the order` `    shuffle(\$numbers);` `    // output the first 6 numbers` `    echo implode(', ', array_slice(\$numbers, 0, GENERATE));` `?>`

Which produces:

36, 27, 30, 2, 47, 29

## Log

• March 28, 2005 - Added solution 1 and 2.
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