Shortest Common Super-sequence Leetcode (Same as Lcs string)

Dp Learnings (27 Part Series)

1 House Robber leetcode problem
2 Jump game leetcode problem
… 23 more parts…
3 Jump game II leetcode problem
4 Cherry Pickup II Leetcode Problem
5 Partition Equals Subset Sum Leetcode problem or Subset sum equals to target
6 Maximum Sum Problem GeeksForGeeks
7 Count Palindrome Sub-Strings of a String GeeksForGeeks
8 Length of Longest Common Subsequence (LCS) and Longest common subsequence string leetcode
9 0/1 Knapsack Problem GeeksForGeeks both bounded and Unbounded
10 Shortest distance from source to all other nodes in a Directed Acyclic Graph
11 Coin change Leetcode
12 Coin Change 2 Leetcode
13 Target Sum or Partition with given difference Leetcode
14 Rod cutting Problem (similar to unbounded knapsack)
15 Length of longest common substring
16 Longest Palindromic subsequence (Same as Lcs)
17 Minimum Insertion steps needed to make a string palindrome (Same as LCS)
18 Minimum number of Insertion and deletion needed to convert String A to String B or make both the strings equal (same as lcs)
19 Shortest Common Super-sequence Leetcode (Same as Lcs string)
20 Distinct Subsequence Leetcode
21 Partition with given difference
22 Two best non overlapping events
23 Longest increasing subsequence
24 Edit distance
25 Maximum product subarray
26 Target sum
27 Maximum Multiplication Score

Given two strings str1 and str2, return the shortest string that has both str1 and str2 as subsequences. If there are multiple valid strings, return any of them.

A string s is a subsequence of string t if deleting some number of characters from t (possibly 0) results in the string s.

Example 1:

Input: str1 = "abac", str2 = "cab"
Output: "cabac"
Explanation: 
str1 = "abac" is a subsequence of "cabac" because we can delete the first "c".
str2 = "cab" is a subsequence of "cabac" because we can delete the last "ac".
The answer provided is the shortest such string that satisfies these properties.

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Solution:
Time complexity is same as that of longest common subsequence
i.e. O(m*n) , space complexity is O(m*n) for using dp array.

class Solution {
    String str = "";
    public String shortestCommonSupersequence(String str1, String str2) {
        int dp[][] = new int[str1.length()+1][str2.length()+1];

        for(int i=0;i<=str1.length();i++){
            dp[i][0] =0;
        }
        for( int i =0;i<=str2.length();i++){
            dp[0][i] = 0;
        }

        for( int i =1;i<=str1.length();i++){
            for(int j =1;j<=str2.length();j++){
                if(str1.charAt(i-1)==str2.charAt(j-1)){
                    dp[i][j] = 1 + dp[i-1][j-1];
                }
                else dp[i][j] = Integer.max(dp[i][j-1],dp[i-1][j]);
            }
        }
        int p = str1.length(), q = str2.length();

        while(p>0 && q>0){
            if(str1.charAt(p-1) == str2.charAt(q-1)){
                str = str1.charAt(p-1)+ str;
                p--;
                q--;

            }
            else if(dp[p][q-1] > dp[p-1][q]){
                str = str2.charAt(q-1) + str;
                q--;
            }
            else {
                str = str1.charAt(p-1) + str;
                p--;
            }
        }

        while(p>0){
            str  = str1.charAt(p-1)+ str;
            p--;
        }
        while(q>0){
            str = str2.charAt(q-1) +  str;
            q--;
        }
        return str;
    }
}

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Dp Learnings (27 Part Series)

1 House Robber leetcode problem
2 Jump game leetcode problem
… 23 more parts…
3 Jump game II leetcode problem
4 Cherry Pickup II Leetcode Problem
5 Partition Equals Subset Sum Leetcode problem or Subset sum equals to target
6 Maximum Sum Problem GeeksForGeeks
7 Count Palindrome Sub-Strings of a String GeeksForGeeks
8 Length of Longest Common Subsequence (LCS) and Longest common subsequence string leetcode
9 0/1 Knapsack Problem GeeksForGeeks both bounded and Unbounded
10 Shortest distance from source to all other nodes in a Directed Acyclic Graph
11 Coin change Leetcode
12 Coin Change 2 Leetcode
13 Target Sum or Partition with given difference Leetcode
14 Rod cutting Problem (similar to unbounded knapsack)
15 Length of longest common substring
16 Longest Palindromic subsequence (Same as Lcs)
17 Minimum Insertion steps needed to make a string palindrome (Same as LCS)
18 Minimum number of Insertion and deletion needed to convert String A to String B or make both the strings equal (same as lcs)
19 Shortest Common Super-sequence Leetcode (Same as Lcs string)
20 Distinct Subsequence Leetcode
21 Partition with given difference
22 Two best non overlapping events
23 Longest increasing subsequence
24 Edit distance
25 Maximum product subarray
26 Target sum
27 Maximum Multiplication Score

原文链接：Shortest Common Super-sequence Leetcode (Same as Lcs string)