somebody see a mistake?



#define MAXINT 2000000000
#include<stdio.h>
#include<math.h>
#include<stdlib.h>


typedef struct{
    int x,y;
    int ID;
    double ang;
}ponto_t;
ponto_t tb[10000];

int sort( const void *a, const void *b){
    ponto_t* ta = (ponto_t*)a;
    ponto_t* tb = (ponto_t*)b;
    if ((ta->x==0) && (ta->y==0)) return -1;
    if ((tb->x==0) && (tb->y==0)) return 1;
       return (ta->x*tb->y - tb->x*ta->y)>0?1:-1;
}


int main(){
    #ifndef ONLINE_JUDGE
        freopen("1207.in","r",stdin);
        freopen("1207.out","w",stdout);
    #endif
    int n,x=MAXINT,themin=0,k;
    scanf("%d",&n);


    for(k=0;k<n;k++){
        scanf("%d %d",&(tb[k].x),&(tb[k].y));
        tb[k].ID=k+1;
        if (tb[k].x<x){
            x=tb[k].x;
            themin=k;
        }
    }
    for(k=0;k<n;k++){
        tb[k].x-=tb[themin].x;
        tb[k].y-=tb[themin].y;
    }


    qsort(tb,n,sizeof(ponto_t),sort);

    printf("%d %d",tb[0].ID,tb[n/2].ID);

    return 0;
}