/**
 * max increasing subsequence
 * @param arr int整型一维数组 the array
 * @return int整型
 */
function MLS( arr ) {
    // write code here
  //注意去重
    if(arr.length === 0){
        return 0
    }
    let ret = 1;
    let max = 0;
    let tempset = arr.sort(function(a,b){
        return a-b;
    })
    let temp = Array.from(new Set(tempset))
    for(let i = 0;i<temp.length;i++){
        if(temp[i] == temp[i-1]){
            continue
        }
        if(temp[i]+1 === temp[i+1]){
            ret++;
        }else{
            ret = 1;
        }
        max = Math.max(ret,max)
    }
    return max
}
module.exports = {
    MLS : MLS
};