/* Sample solution to extreme edge. */

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>


#define MAX_P_SIZE   100
#define MIN_P_SIZE   3
#define MAX_XY_VALUE 10000

static int PX[MAX_P_SIZE];
static int PY[MAX_P_SIZE];

int LeftOf( int a, int b, int c )
{
     if( (((PX[b] - PX[a]) * (PY[c] - PY[a])) - 
	  ((PX[c] - PX[a]) * (PY[b] - PY[a]))) > 0 ) {
	  return( 1 );
     } else {
	  return( 0 );
     }
}

int main( int argc, char* argv[] )
{
     char buffer[256];
     int n = 0;
     int i = 0;
     int j = 0;
     int bottomRightVertex = MAX_P_SIZE;
     int extremeEdgeVertex = MAX_P_SIZE;
     int checkVertex       = MAX_P_SIZE;
     int          edgePos           = -1;
     
     /* Input. */
     fgets( buffer, 256, stdin );
     sscanf( buffer, "%d", &n );
     assert( (MIN_P_SIZE <= n) && (n <= MAX_P_SIZE) );
     printf( "I got %d points.\n", n );
     for( i=0; i < n; i+=1 ) {
	  fgets( buffer, 256, stdin );
	  sscanf( buffer, "%d %d", PX + i, PY + i );
	  assert( (*(PX + i) < MAX_XY_VALUE) && (*(PY + i) < MAX_XY_VALUE) );
	  printf( "(%d, %d)\n", PX[i], PY[i] );
     }

     /* Step 1:  Find bottom right vertex v. */
     bottomRightVertex = 0;
     for( i=1; i < n; i+=1 ) {
	  if( (PY[i] < PY[bottomRightVertex]) ||
	      ((PY[i] == PY[bottomRightVertex]) && 
	       (PX[i] > PX[bottomRightVertex])) ) {
	       bottomRightVertex = i;
	  }
     }
     printf( "Bottom right vertex is %d = (%d, %d)\n",
	     bottomRightVertex,
	     PX[bottomRightVertex],
	     PY[bottomRightVertex] );
     
     /* Step 2:  Form an edge vx, for some x in P\{v}.
	         Determine whether 
		 LeftOf(v,x,y_1)=LeftOf(v,x,y_2)=...=LeftOf(v,x,y_(n-2).
	         If so, vx is an extreme edge. */
     for( i=1; i < n; i+=1 ) {
	  extremeEdgeVertex = (bottomRightVertex + i) % n;
	  edgePos = -1;
	  for( j=1; j < n; j+=1 ) {
	       checkVertex = (j + i) % n;
	       if( (checkVertex != extremeEdgeVertex) ) {
		    printf( "Checking %d, %d, %d.\n",
			    bottomRightVertex,
			    extremeEdgeVertex,
			    checkVertex );
		    if( edgePos < 0 ) {
			 edgePos = LeftOf( bottomRightVertex,
					   extremeEdgeVertex,
					   checkVertex );
			 printf( "This is the reference point. LeftOf = %d\n", edgePos );

		    } else if ( edgePos != LeftOf( bottomRightVertex,
						   extremeEdgeVertex,
						   checkVertex ) ) {
			 printf( "Mismatch, try next point.\n\n" );
			 edgePos = -1;
			 break;
		    }
	       }
	  }
	  if( edgePos >= 0 ) {
	       /* Output extreme edge. */
	       printf( "%d\n%d\n", bottomRightVertex, extremeEdgeVertex );
	       break;
	  }
     }

     return( 0 );
}