#include <iostream>
#include <stdio.h>
#include <algorithm>
using namespace std;
typedef long long Int;

struct triangle
{
    Int x1,y1,x2,y2,x3,y3;
    Int side1,side2,side3;
};

struct fraction
{
    Int a,b;
};

triangle tri[100001];
Int rtL=0;
triangle rtri[100001];
fraction fractions[100001];

bool SortFrac(fraction ch,fraction zn)
{
    fraction ca=ch,cb=zn;

    ca.a=ca.a * cb.b;
    cb.a=cb.a * ca.b;

    return (ca.a<=cb.a);
}

int main()
{
    freopen("tri.in","r",stdin);
    freopen("tri.out","w",stdout);

    Int n;
    Int i;
    Int curlen=1;
    Int maxlen=1;
    Int d;
    fraction copy1,copy2;

    scanf("%I64d",&n);

    for (i=1;i<=n;i++)
    {
        scanf("%I64d %I64d %I64d %I64d %I64d %I64d",&tri[i].x1,&tri[i].y1,&tri[i].x2,&tri[i].y2,&tri[i].x3,&tri[i].y3);

        tri[i].side1=(tri[i].x1 - tri[i].x2)*(tri[i].x1 - tri[i].x2) + (tri[i].y1 - tri[i].y2)*(tri[i].y1 - tri[i].y2);
        tri[i].side2=(tri[i].x2 - tri[i].x3)*(tri[i].x2 - tri[i].x3) + (tri[i].y2 - tri[i].y3)*(tri[i].y2 - tri[i].y3);
        tri[i].side3=(tri[i].x3 - tri[i].x1)*(tri[i].x3 - tri[i].x1) + (tri[i].y3 - tri[i].y1)*(tri[i].y3 - tri[i].y1);

        if (tri[i].side1==tri[i].side2)
        {
            rtL++;
            rtri[rtL]=tri[i];
        }
        else if (tri[i].side1==tri[i].side3)
        {
            rtL++;
            rtri[rtL].x1=tri[i].x1;
            rtri[rtL].x2=tri[i].x2;
            rtri[rtL].x3=tri[i].x3;
            rtri[rtL].y1=tri[i].y1;
            rtri[rtL].y2=tri[i].y2;
            rtri[rtL].y3=tri[i].y3;

            rtri[rtL].side1=tri[i].side1;
            rtri[rtL].side2=tri[i].side3;
            rtri[rtL].side3=tri[i].side2;
        }
        else if (tri[i].side2==tri[i].side3)
        {
            rtL++;
            rtri[rtL].x1=tri[i].x1;
            rtri[rtL].x2=tri[i].x2;
            rtri[rtL].x3=tri[i].x3;
            rtri[rtL].y1=tri[i].y1;
            rtri[rtL].y2=tri[i].y2;
            rtri[rtL].y3=tri[i].y3;

            rtri[rtL].side1=tri[i].side2;
            rtri[rtL].side2=tri[i].side3;
            rtri[rtL].side3=tri[i].side1;
        }
    }

    for (i=1;i<=rtL;i++)
    {
        fractions[i].a=rtri[i].side1;
        fractions[i].b=rtri[i].side3;
    }

    sort(fractions+1,fractions+1+rtL,SortFrac);

    for (i=2;i<=rtL;i++)
    {
        copy1=fractions[i-1];
        copy2=fractions[i];

        copy1.a=copy1.a * copy2.b;
        copy2.a=copy2.a * copy1.b;

        if (copy1.a==copy2.a)
        {
            curlen++;
            if (curlen>maxlen)
            {
                maxlen=curlen;
            }
        }
        else
        {
            curlen=1;
        }
    }

    printf("%I64d\n",maxlen);
}
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