Q34 Longest Common Substring | Practice | GeeksforGeeks

PHOTO

Sun Mar 26 2023 13:09:31 GMT+0000 (Coordinated Universal Time)

Saved by @Ayush_dabas07

//{ Driver Code Starts
//Initial Template for Java

import java.io.*;
import java.util.*;

class GFG
{
    public static void main(String args[])throws IOException
    {
        BufferedReader read = new BufferedReader(new InputStreamReader(System.in));
        int t = Integer.parseInt(read.readLine());
        while(t-- > 0)
        {
            String input[] = read.readLine().trim().split(" ");
            int n = Integer.parseInt(input[0]);
            int m = Integer.parseInt(input[1]);
            
            String S1 = read.readLine().trim();
            String S2 = read.readLine().trim();

            Solution ob = new Solution();
            System.out.println(ob.longestCommonSubstr(S1, S2, n, m));
        }
    }
}
// } Driver Code Ends


//User function Template for Java

class Solution{
    int longestCommonSubstr(String s1, String s2, int m, int n){
        /* Q34 of dp playlist , compare all prefixes of both s1 and s2 and find longest
        common suffix , that will become your longest common substring
        */
        
        int dp[][] = new int[m+1][n+1];
        int ans = 0;
        
        //first coloumn and first row will be 0 , which is by default also 0
        
        for(int i = 1 ; i < m+1 ; i++){
            
            for(int j = 1 ; j < n+1; j++){
                
                //if last chars are equal , ans = ansof(prefix) + 1 , ans of prefix
                //can be found diagonally behind
                if(s1.charAt(i-1) == s2.charAt(j-1)){
                    dp[i][j] = dp[i-1][j-1] + 1;
                    ans = Math.max(ans , dp[i][j]);
                }
                
            }
        }
        
        // for(int i = 0 ; i < m ; i++){
        //     for(int j = 0 ; j<n ; j++){
        //         System.out.print(dp[i][j] + " ");
        //     }
        //     System.out.println();
        // }
        
        return ans;
    }
}

https://practice.geeksforgeeks.org/problems/longest-common-substring1452/1

Save snippets that work from anywhere online with our extensions

Available in the Chrome Web Store

Get Firefox Add-on

Get VS Code extension

Comments

More like this

DP level 2

@Ayush_dabas07

Q66 Distinct Echo Substrings - LeetCode 1316 (rabin karp rolling hash -> O(n^2)) Q66 Distinct Echo Substrings - LeetCode 1316(O(n^3) solution) Q65 Interleaving String - LeetCode 97 Q64 Frog Jump - LeetCode 403 Q63 Champagne Tower - LeetCode 799 Q62 Super Ugly Number - LeetCode 313 Q61 Ugly Number 2 - LeetCode 264 Q60 Minimum Insertion Steps to Make a String Palindrome - LeetCode 1316 Q59 Temple Offerings | Practice | GeeksforGeeks Q58 Word Break - LeetCode 139 Q57 Arithmetic Slices II - Subsequence - LeetCode 446 Q56 Arithmetic Slices - LeetCode 413 Q55 Max sum of M non-overlapping subarrays of size K - GeeksforGeeks (tabulization) Q55 Max sum of M non-overlapping subarrays of size K - GeeksforGeeks (memoization) Q54 Maximum Sum of 3 Non-Overlapping Subarrays - LeetCode 689 Q53 Maximum Sum of Two Non-Overlapping Subarrays - LeetCode 1031 Q52 Maximum difference of zeros and ones in binary string | Practice | GeeksforGeeks Q51 Mobile numeric keypad | Practice | GeeksforGeeks Q50 Distinct Transformation LeetCode Playground ( tabulization approach) Q50 - Distinct Transformation- LeetCode Playground ( recursion + memoization approach) Q49 Highway BillBoards - Coding Ninjas Codestudio approach 2 Q49 Highway BillBoards - Coding Ninjas Codestudio (approach 1 LIS) Q48 Knight Probability in Chessboard - LeetCode 688 Q47 Cherry Pickup - LeetCode 741 (recursion approach) Q46 Super Egg Drop - LeetCode 887 Q45 Predict the Winner - LeetCode 486 Q45 Optimal Strategy For A Game | Practice | GeeksforGeeks | leetcode 46 Q44 Largest Sum Subarray of Size at least K | Practice | GeeksforGeeks Q42 Maximum Subarray - LeetCode 53 Q41 Minimum Cost To Make Two Strings Identical | Practice | GeeksforGeeks Q40 Minimum ASCII Delete Sum for Two Strings - LeetCode 712 Q39 Scramble String - LeetCode 87 Q38 Edit Distance - LeetCode 72 Q37 Regular Expression Matching - LeetCode 10 Q36 Wildcard Matching - LeetCode Q35 Longest Repeating Subsequence | Practice | GeeksforGeeks Q34 Longest Common Substring | Practice | GeeksforGeeks Q33 Count Different Palindromic Subsequences - LeetCode 730 Q32 Number of distinct subsequences | Practice | GeeksforGeeks Q31 Longest Palindromic Substring - LeetCode Q30 Count Palindromic Subsequences | Practice | GeeksforGeeks Q29 Longest Palindromic Subsequence - LeetCode 516 Q28 Longest Common Subsequence - LeetCode 1143 Q27 Minimum Score Triangulation of Polygon - LeetCode 1039 Q26 Optimal binary search tree | Practice | GeeksforGeeks Q24 Matrix Chain Multiplication | Practice | GeeksforGeeks Q23 Palindrome Partitioning II - LeetCode 132 Q23 Palindrome Partitioning II - LeetCode - 132 ( n^3 approach) Q22 Palindromic Substrings - LeetCode 647 Q21 Rod Cutting | Practice | GeeksforGeeks Q20 Minimum Score Triangulation of Polygon - LeetCode 1039 Q19 Intersecting Chords in a Circle | Interviewbit Q18 Generate Parentheses - LeetCode 22 Q17 PepCoding | Count Of Valleys And Mountains Q16 Unique Binary Search Trees - LeetCode 96 Q15 Catalan Number Minimum Score of a Path Between Two Cities - 2492 Q14 Perfect Squares - LeetCode Q13 Russian Doll Envelopes - LeetCode (LIS in NlogN - accepted solution) Q13 Russian Doll Envelopes - LeetCode 354 solution1(LIS in O(n^2)) Q12 PepCoding | Maximum Non-overlapping Bridges Q11 Longest Bitonic subsequence | Practice | GeeksforGeeks Q10 Maximum sum increasing subsequence | Practice | GeeksforGeeks Q9 PepCoding | Print All Longest Increasing Subsequences Q8 Longest Increasing Subsequence - LeetCode 300 Q7 2 Keys Keyboard - LeetCode 650 Q-6 PepCoding | Print All Results In 0-1 Knapsack Q5 PepCoding | Print All Paths With Target Sum Subset Q4 PepCoding | Print All Paths With Maximum Gold Q3 PepCoding | Print All Paths With Minimum Cost Q2 Jump Game II - LeetCode 45 Q1 Maximal Square - LeetCode 221 Q67 Longest Increasing Subsequence - LeetCode 300 ( LIS O(nlogn) solution) Q43 K-Concatenation Maximum Sum - LeetCode 1191 Q13 Russian Doll Envelopes - LeetCode 354 ( LIS -> O(nlogn) solution) Q25 Burst Balloons - LeetCode 312

Browse more snippets >>