RosettaCodeData/Task/Look-and-say-sequence/JavaScript/look-and-say-sequence-2.js

14 lines
290 B
JavaScript

function lookAndSay( s="" ){
var tokens=[]
var i=0, j=1
while( i<s.length ) {
while( j<s.length && s[j]===s[i] ) j++
tokens.push( `${j-i}${s[i]}` )
i=j++
}
return tokens.join("")
}
var phrase="1"
for(var n=0; n<10; n++ )
console.log( phrase = lookAndSay( phrase ) )