# Robson » Little Red Book » Odd or even

## Chapter 4 - Question 1

Produce a program that reports whether or not an input integer is odd or even.

### Solution 1

`<?`
`    // generate a random number`
`    \$number = mt_rand(1, 100);`
`    `
`    // divide the number by two and see if anything is left`
`    // if so, it must be an odd number, because even numbers can always be divided by two perfectly`
`    if (\$number % 2)`
`        // show that the number is odd`
`        echo \$number . ' is odd.';`
`    else`
`        // show that the number is even`
`        echo \$number . ' is even.';            `
`?>`

Which produces:

51 is odd.

### Solution 2

Here's a c++ solution:

`#include <iostream.h>`
`int main ()`
`{`
`    int i;`
`    cout << "Type a number or 0 to exit\n>";`
`    cin >> i;`
`    if (i%2)`
`        cout << "That number is odd.\n";`
`    else`
`        cout << "That number is even.\n";`
`    return 0;`
`}`

## Log

• March 28, 2005 - Added solution 2.
• Jan 30, 2005 - Added solution 1.
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