原文:

给定 n 个元素,编写一个程序,打印相邻元素差为 1 的最长递增子序列。 例:

输入:a[] = {3,10,3,11,4,5,6,7,8,12} 输出:3 4 5 6 7 8 说明:3,4,5,6,7,8 是相邻元素相差 1 的最长递增子序列。 输入:a[] = {6,7,8,3,4,5,9,10} 输出:6 7 8 9 10 说明:6,7,8,9,10 是最长的递增子序列

我们已经讨论了的长度。为了打印子序列,我们存储最后一个元素的索引。然后我们打印以最后一个元素结尾的连续元素。 下面给出的是上述方法的实施:

c

// cpp program to find length of the
// longest increasing subsequence
// whose adjacent element differ by 1
#include 
using namespace std;
// function that returns the length of the
// longest increasing subsequence
// whose adjacent element differ by 1
void longestsubsequence(int a[], int n)
{
    // stores the index of elements
    unordered_map mp;
    // stores the length of the longest
    // subsequence that ends with a[i]
    int dp[n];
    memset(dp, 0, sizeof(dp));
    int maximum = int_min;
    // iterate for all element
    int index = -1;
    for (int i = 0; i < n; i  ) {
        // if a[i]-1 is present before i-th index
        if (mp.find(a[i] - 1) != mp.end()) {
            // last index of a[i]-1
            int lastindex = mp[a[i] - 1] - 1;
            // relation
            dp[i] = 1   dp[lastindex];
        }
        else
            dp[i] = 1;
        // stores the index as 1-index as we need to
        // check for occurrence, hence 0-th index
        // will not be possible to check
        mp[a[i]] = i   1;
        // stores the longest length
        if (maximum < dp[i]) {
            maximum = dp[i];
            index = i;
        }
    }
    // we know last element of sequence is
    // a[index]. we also know that length
    // of subsequence is "maximum". so we
    // print these many consecutive elements
    // starting from "a[index] - maximum   1"
    // to a[index].
    for (int curr = a[index] - maximum   1;
         curr <= a[index]; curr  )
        cout << curr << " ";
}
// driver code
int main()
{
    int a[] = { 3, 10, 3, 11, 4, 5, 6, 7, 8, 12 };
    int n = sizeof(a) / sizeof(a[0]);
    longestsubsequence(a, n);
    return 0;
}

java 语言(一种计算机语言,尤用于创建网站)

// java program to find length of the
// longest increasing subsequence
// whose adjacent element differ by
import java.util.hashmap;
class gfg
{
    // function that returns the length of the
    // longest increasing subsequence
    // whose adjacent element differ by 1
    public static void longestsubsequence(int[] a,
                                          int n)
    {
        // stores the index of elements
        hashmap mp = new hashmap<>();
        // stores the length of the longest
        // subsequence that ends with a[i]
        int[] dp = new int[n];
        int maximum = integer.min_value;
        // iterate for all element
        int index = -1;
        for(int i = 0; i < n; i  )
        {
            // if a[i]-1 is present before i-th index
            if (mp.get(a[i] - 1) != null)
            {
                // last index of a[i]-1
                int lastindex = mp.get(a[i] - 1) - 1;
                // relation
                dp[i] = 1   dp[lastindex];
            }
            else
                dp[i] = 1;
            // stores the index as 1-index as we need to
            // check for occurrence, hence 0-th index
            // will not be possible to check
            mp.put(a[i], i    1);
            // stores the longest length
            if (maximum < dp[i])
            {
                maximum = dp[i];
                index = i;
            }
        }
        // we know last element of sequence is
        // a[index]. we also know that length
        // of subsequence is "maximum". so we
        // print these many consecutive elements
        // starting from "a[index] - maximum   1"
        // to a[index].
        for (int curr = a[index] - maximum   1;
            curr <= a[index]; curr  )
            system.out.print(curr   " ");
    }
    // driver code
    public static void main(string[] args)
    {
        int[] a = { 3, 10, 3, 11, 4,
                    5, 6, 7, 8, 12 };
        int n = a.length;
        longestsubsequence(a, n);
    }
}
// this code is contributed by sanjeev2552

python 3

# python 3 program to find length of
# the longest increasing subsequence
# whose adjacent element differ by 1
import sys
# function that returns the length
# of the longest increasing subsequence
# whose adjacent element differ by 1
def longestsubsequence(a, n):
    # stores the index of elements
    mp = {i:0 for i in range(13)}
    # stores the length of the longest
    # subsequence that ends with a[i]
    dp = [0 for i in range(n)]
    maximum = -sys.maxsize - 1
    # iterate for all element
    index = -1
    for i in range(n):
        # if a[i]-1 is present before
        # i-th index
        if ((a[i] - 1 ) in mp):
            # last index of a[i]-1
            lastindex = mp[a[i] - 1] - 1
            # relation
            dp[i] = 1   dp[lastindex]
        else:
            dp[i] = 1
        # stores the index as 1-index as we
        # need to check for occurrence, hence
        # 0-th index will not be possible to check
        mp[a[i]] = i   1
        # stores the longest length
        if (maximum < dp[i]):
            maximum = dp[i]
            index = i
    # we know last element of sequence is
    # a[index]. we also know that length
    # of subsequence is "maximum". so we
    # print these many consecutive elements
    # starting from "a[index] - maximum   1"
    # to a[index].
    for curr in range(a[index] - maximum   1,
                      a[index]   1, 1):
        print(curr, end = " ")
# driver code
if __name__ == '__main__':
    a = [3, 10, 3, 11, 4, 5,
                6, 7, 8, 12]
    n = len(a)
    longestsubsequence(a, n)
# this code is contributed by
# surendra_gangwar

c

// c# program to find length of the
// longest increasing subsequence
// whose adjacent element differ by
using system;
using system.collections.generic;
class gfg
{
    // function that returns the length of the
    // longest increasing subsequence
    // whose adjacent element differ by 1
    static void longestsubsequence(int[] a, int n)
    {
        // stores the index of elements
        dictionary mp = new dictionary();
        // stores the length of the longest
        // subsequence that ends with a[i]
        int[] dp = new int[n];
        int maximum = -100000000;
        // iterate for all element
        int index = -1;
        for(int i = 0; i < n; i  )
        {
            // if a[i]-1 is present before i-th index
            if (mp.containskey(a[i] - 1) == true)
            {
                // last index of a[i]-1
                int lastindex = mp[a[i] - 1] - 1;
                // relation
                dp[i] = 1   dp[lastindex];
            }
            else
                dp[i] = 1;
            // stores the index as 1-index as we need to
            // check for occurrence, hence 0-th index
            // will not be possible to check
            mp[a[i]] = i   1;
            // stores the longest length
            if (maximum < dp[i])
            {
                maximum = dp[i];
                index = i;
            }
        }
        // we know last element of sequence is
        // a[index]. we also know that length
        // of subsequence is "maximum". so we
        // print these many consecutive elements
        // starting from "a[index] - maximum   1"
        // to a[index].
        for (int curr = a[index] - maximum   1;
            curr <= a[index]; curr  )
            console.write(curr   " ");
    }
    // driver code
    static void main()
    {
        int[] a = { 3, 10, 3, 11, 4,
                    5, 6, 7, 8, 12 };
        int n = a.length;
        longestsubsequence(a, n);
    }
}
// this code is contributed by mohit kumar

java 描述语言


输出:

3 4 5 6 7 8 

时间复杂度:o(nlogn) t3】辅助空间: o(n)