Largest square formed in a matrix

PROBLEM :

Given a binary matrix, find out the maximum size square sub-matrix with all 1s.

Input:

The first line of input contains an integer T denoting the number of test cases.
The first line of each test case is n and m,n is the number of rows and m is the number of columns.
The second line of each test case contains array C[n][m] in row major form.

Output:

Print maximum size square sub-matrix.

Constraints:

1 = T = 100
1 = n,m = 50
0 = C[n][m] = 1

Example:

Input:
3
5 6
0 1 0 1 0 1 1 0 1 0 1 0 0 1 1 1 1 0 0 0 1 1 1 0 1 1 1 1 1 1
2 2
1 1 1 1
2 2
0 0 0 0

Output:
3
2
0

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

#include<iostream>
using namespace std;
#define R 50
#define C 50
int Largest_square(int mat[R][C],int ,int ) ;
int min(int ,int ,int ) ;
int main()
 {
int t,r,c,ans,i,j,mat[R][C] ;
cin>>t ;
while(t--)
{
   cin>>r>>c ;
   for(i=0;i<r;i++)
       for(j=0;j<c;j++)
           cin>>mat[i][j] ;
         
   ans=Largest_square(mat,r,c) ;
   cout<<ans<<endl ;
}
return 0;
}

int Largest_square(int mat[R][C],int r,int c)
{
    int d[r+1][c+1] ;
    int i,j,mx ;
   
    for(i=0;i<=c;i++)
        d[0][i]=0 ;
       
    for(j=0;j<=r;j++)
        d[j][0]=0 ;
       
    for(i=1;i<=r;i++)
    {
        for(j=1;j<=c;j++)
        {
            if(mat[i-1][j-1]==0)
                d[i][j]=0 ;
            else
                d[i][j]=1+min(d[i-1][j-1],d[i-1][j],d[i][j-1]) ;
        }
    }
   
    mx=d[0][0] ;
    for(i=0;i<=r;i++)
    {
        for(j=0;j<=c;j++)
        {
            if(mx<d[i][j])
                mx=d[i][j] ;
        }
    }
   
    return mx ;
}

int min(int a,int b,int c)
{
    int temp ;
    temp=a<b?a:b ;
    return c<temp?c:temp ;
}

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