#include<fstream.h>
#define Nmax 4001

int b[Nmax],c[Nmax],viz[Nmax];

struct kafka {
   int bir,cul; } T[Nmax];

long t,timp;


int main()
{
int i,j,l,poz,nb,nc,bs,cs;

ifstream f("kafka.in");
ofstream g("kafka.out");

f>>nb>>nc>>bs>>t;

for(i=1;i<=nb*nc;i++)
 f>>c[i]>>b[i];

   cs=1,timp=1;

  do {

    T[timp].bir=bs;
    T[timp++].cul=cs;

    viz[(bs-1)*nc+cs]=1;


    poz = (bs-1)*nc+cs;

    bs=b[poz], cs=c[poz];


	} while ( !viz[(bs-1)*nc+cs] && timp-1 <= t );

	T[timp].bir=bs;
	T[timp].cul=cs;


    if( timp < t )
	  {

 for(i=timp-1 ;( T[i].bir != T[timp].bir) || (T[i].cul!=T[timp].cul) ; i-- );


    l=timp-i;

    t=t-i+1;
    t=(t-1)%l+1;

    g<<T[i+t-1].bir<<"\n";
	  }
	 else
	g<<T[t].bir<<"\n";


 f.close();
  g.close();

 return 0;
 }