Find Palindrome of String

#include<stdio.h>
#include<conio.h>
#include<string.h>

char a[20];
int l;

int palin(int num)
{
 if(num>l/2)
  return 1;
 if(a[num] == a[l-num-1])
  return palin(num+1);
 else
  return 0;
}


void main()
{
 clrscr();
 printf("Enter a String : ");
 gets(a);
 l = strlen(a);
 int ret = palin(0);
 if(ret == 1)
  printf("\n Palindrome");
 else
  printf("\n Not Palindrome");
 getch();
}

Finding Eigenvalue

#include<iostream.h>
//#include<conio.h>
#include<math.h>
#define max 2

class matrix
{
  private :
 int num[max][max];
 int rt1,rt2;
 int egn1[max][1],egn2[max][1];
  public :
 void inp_mat()
 {
  cout<<"\n\n Enter the elements in the matrix";
  for(int i=0;i<max;i++)
  {
   cout<<"\n Enter elements for Row#"<<i+1<<" : ";
   for(int j=0;j<max;j++)
    cin>>num[i][j];
  }
 }
 void fnd_egn()
 {
  int a,b,c,det,quo;
  a = 1;
  b = -(num[0][0]+num[1][1]);
  c = (num[0][0]*num[1][1])-(num[0][1]*num[1][0]);
  cout<<"\n Its' characterristic equation is : "<<a<<"*x*x + "<<b<<"*x +"<<c;
  det = b*b - 4*a*c;
  rt1 = (-b+sqrt(det))/(2*a);
  rt2 = (b+sqrt(det))/(2*a);
  cout<<"\n\n And, the Eigenvalues are : "<<rt1<<" and "<<rt2;
  a = num[0][0] - rt1;
  b = num[0][1];
 quo = a>b?-a/b:-b/a;
  if(quo>0)
  {
   egn1[0][0] = quo;
   egn1[1][0] = 1;
  }
  else
  {
   egn1[1][0] = quo;
   egn1[0][0] = 1;
  }
  cout<<"\n\n The Eigenvector correspoding to Eigenvalue "<<rt1;
  cout<<"\n\n\t\t"<<egn1[0][0]<<"\n\t\t"<<egn1[1][0];
  a = num[0][0] - rt2;
  b = num[0][1];
  quo = a>b?-a/b:-b/a;
  if(quo>0)
  {
   egn2[0][0] = quo;
   egn2[1][0] = 1;
  }
  else
  {
   egn2[1][0] = quo;
   egn2[0][0] = 1;
  }
  cout<<"\n\n The Eigenvector correspoding to Eigenvalue "<<rt2;
  cout<<"\n\n\t\t"<<egn2[0][0]<<"\n\t\t"<<egn2[1][0];
 }
};

int main()
{
 //clrscr();
 matrix mat;
 mat.inp_mat();
 mat.fnd_egn();
// getch();
 return 0;
}