RosettaCodeData/Task/Longest-increasing-subsequence/JavaScript/longest-increasing-subseque...

39 lines
1.0 KiB
JavaScript

var _ = require('underscore');
function findIndex(input){
var len = input.length;
var maxSeqEndingHere = _.range(len).map(function(){return 1;});
for(var i=0; i<len; i++)
for(var j=i-1;j>=0;j--)
if(input[i] > input[j] && maxSeqEndingHere[j] >= maxSeqEndingHere[i])
maxSeqEndingHere[i] = maxSeqEndingHere[j]+1;
return maxSeqEndingHere;
}
function findSequence(input, result){
var maxValue = Math.max.apply(null, result);
var maxIndex = result.indexOf(Math.max.apply(Math, result));
var output = [];
output.push(input[maxIndex]);
for(var i = maxIndex ; i >= 0; i--){
if(maxValue==0)break;
if(input[maxIndex] > input[i] && result[i] == maxValue-1){
output.push(input[i]);
maxValue--;
}
}
output.reverse();
return output;
}
var x = [0, 7, 8, 4, 12, 2, 10, 6, 14, 1, 9, 5, 13, 3, 11, 7, 15];
var y = [3, 2, 6, 4, 5, 1];
var result = findIndex(x);
var final = findSequence(x, result);
console.log(final);
var result1 = findIndex(y);
var final1 = findSequence(y, result1);
console.log(final1);