Longest Common Substring

PROBLEM :
Given two strings ‘X’ and ‘Y’, find the length of the longest common substring.

Examples :

Input : X = "GeeksforGeeks", y = "GeeksQuiz"
Output : 5
The longest common substring is "Geeks" and is of
length 5.

Input : X = "abcdxyz", y = "xyzabcd"
Output : 4
The longest common substring is "abcd" and is of
length 4.

Input : X = "zxabcdezy", y = "yzabcdezx"
Output : 6
The longest common substring is "abcdez" and is of
length 6.

Input:
First line of the input contains no of test cases  T,the T test cases follow.
Each test case consist of 2 space separated integers A and B denoting the size of string X and Y respectively
The next two lines contains the 2 string X and Y.

Output:
For each test case print the length of longest  common substring of the two strings .

Constraints:
1<=T<=30
1<=size(X),size(Y)<=100

Example:
Input:
2
6 6
ABCDGH
ACDGHR
3 2
ABC
AC

Output:
4
1

--------------------------------------------------------------------------------
SIMPLE c++ IMPLEMENTATION :
--------------------------------------------------------------------------------

#include<iostream>
using namespace std;
#include<string.h>
int Longest_Common_Substring(string ,string ,int ,int ) ;
int main()
{
    int t,n1,n2 ;
    string str1,str2 ;
    cin>>t ;
    while(t--)
    {
        cin>>n1>>n2 ;
        cin>>str1>>str2 ;
        cout<<Longest_Common_Substring(str1,str2,n1,n2)<<endl ;
    }
return 0;
}

int Longest_Common_Substring(string str1,string str2,int n1,int n2)
{
    int temp[n1+1][n2+1] ;
    int i,j,max  ;
   
    max=0 ;
   
    for(i=0;i<=n1;i++)
    {
        for(j=0;j<=n2;j++)
        {
            if(i==0||j==0)
                temp[i][j]=0 ;
            else if(str1[i-1]==str2[j-1])
                temp[i][j]=temp[i-1][j-1]+1 ;
            else
                temp[i][j]=0 ;
               
            max=max>temp[i][j]?max:temp[i][j] ;
        }
    }
    return max ;
}

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