最长递增子序列，时间复杂度（O（nlogn））

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package com.kailong.datastures;import java.util.Arrays;/** * Created by Administrator on 2017/4/17. * 最长递增子序列 */public class FindMaxIntLong {    public static int[] getList1(int []arr){        if(arr==null||arr.length==0){            return null;        }        int []dp=getdp1(arr);        System.out.println(Arrays.toString(dp));        return generateLIS(arr,dp);    }    private static int[] generateLIS(int[] arr, int[] dp) {        int len=0;        int index=0;        for(int i=0;i<dp.length;i++){            if(dp[i]>len){                len=dp[i];                index=i;            }        }        int[] lis=new int[len];        lis[--len]=arr[index];        for(int i=index;i>=0;i--){           if(arr[i]<arr[index]&&dp[i]==dp[index]-1){                lis[--len]=arr[i];                index=i;           }        }        return lis;    }    private static int[] getdp1(int[] arr) {        int[] dp=new int[arr.length];        for(int i=0;i<arr.length;i++){            dp[i]=1;            for(int j=0;j<i;j++){                if(arr[i]>arr[j]){                    dp[i]=Math.max(dp[i],dp[j]+1);                }            }        }        return dp;    }    private static int [] getdp2(int []arr){        int[] dp=new int[arr.length];        int [] ends=new int[arr.length];        ends[0]=arr[0];        dp[0]=1;        int right=0,l=0,r=0,m=0;        for(int i=1;i<arr.length;i++){            l=0;            r=right;            while (l <= r) {                m = (l + r) / 2;                if (arr[i] > ends[m]) {                    l = m + 1;                } else {                    r = m - 1;                }            }            right = Math.max(right, l);            ends[l] = arr[i];            dp[i] = l + 1;        }        return dp;    }    private static int[] getList2(int[] arr) {        if(arr==null||arr.length==0){            return null;        }        int []dp=getdp2(arr);        System.out.println(Arrays.toString(dp));        return generateLIS(arr,dp);    }    public static void main(String []args){        int [] ss={2,3,6,3,7,2,7,9,4,0,1,34,56,3,0,2,2,2,4,77,84,3838,2,288,1727,16,67,2,87282,8228,22,82,2,81,8,34,5,8};        int[] result1 = getList1(ss);        int []result2=getList2(ss);        System.out.println(Arrays.toString(result1));        System.out.println(Arrays.toString(result2));    }}
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