Sha256: 138f897ff9388813bf722a0b7153193ece42d9100c3d5b430694eb3938968bdb
Contents?: true
Size: 827 Bytes
Versions: 72
Compression:
Stored size: 827 Bytes
Contents
/**
* Here is an example solution for the Luhn exercise
*/
component {
function valid( input ) {
// Remove whitespace
input = input.reReplace( '\s', '', 'all' );
// Any non numeric chars means invalid
if( input.reFindNoCase( '[^0-9]' ) ) {
return false;
}
// A single 0 is invalid
if( compare( input, '0' ) == 0 ) {
return false;
}
var accumulator = [];
var oddEven = 0;
// Loop backwards over the digits
for( var i=input.len(); i>0; i-- ) {
var digit = input[ i ];
// Double every other one
if( ++oddEven%2 == 0 ) {
var doubleDigit = digit*2;
accumulator.prepend( ( doubleDigit > 9 ? doubleDigit-9 : doubleDigit ) );
} else {
accumulator.prepend( digit );
}
}
// Is the sum of the digits divisible by 10?
return accumulator.sum() % 10 == 0;
}
}
Version data entries
72 entries across 71 versions & 1 rubygems