Original title:
Given an unordered sequence of integers, find the longest sequence of consecutive numbers.
For example:
Given [100, 4, 200, 1, 3, 2],
The longest sequence of consecutive numbers is [1, 2, 3, 4].
The solution given by Xiaocai:
The code copy is as follows:
function maxSequence(array,step){
var _array = array.slice(), //clone array
_step = 1,
_arrayTemp = [],
i = 0;
var parseLogic = {
//result container
parseResults: [],
//set value to array,what's the last array of parseResults
set: function(n){
this.parseResults[this.parseResults.length-1].push(n);
},
//get the last array from parseResults
get: function(){
return this.parseResults[this.parseResults.length-1];
},
//put a new array in parseResults
addItem: function(){
this.parseResults.push([]);
},
//sort parseResults
sortByAsc: function(){
this.parseResults.sort(function(a,b){
return a.length - b.length;
});
}
};
//check params
_step = step || _step;
//sort array by asc
_array.sort(function(a,b){
return a - b;
});
//remove repeat of data
for(i = 0;i<_array.length;i++){
if(_array[i] != _array[i+1]){
_arrayTemp.push(_array[i]);
}
}
_array = _arrayTemp.slice();
_arrayTemp = [];
//parse array
parseLogic.addItem();
for(i = 0;i<_array.length;i++){
if(_array[i]+_step == _array[i+1]){
parseLogic.set(_array[i]);
continue;
}
if(_array[i]-_step == _array[i-1]){
parseLogic.set(_array[i]);
parseLogic.addItem();
}
}
//sort result
parseLogic.sortByAsc();
//get the max sequence
return parseLogic.get();
}
Call instructions:
Method name:
maxSequence(array, step)
Parameter description:
array: The array to be found. necessary.
step: Sequence step (increment). Optional, default is 1.
Return value:
This method does not change the incoming array and returns a new array containing the largest sequence.
Call example:
maxSequence([5,7,2,4,0,3,9],1); //return [2,3,4,5]
maxSequence([5,7,2,4,0,3,9],2); //return [5,7,9]