#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
using namespace std;
typedef long long lld;

struct Point
{
    lld x,y;
};

Point box[20002];
lld n,m,k;
Point temp[20002];
Point robot[20002];

vector<Point> current, svr;

bool SH(Point a, Point b)
{
    if (a.x != b.x) return a.x<b.x;
    return a.y<b.y;
}

void RollBack()
{
    lld i;
    for (i=0;i<20002;i++)
    {
        robot[i].x = 0;
        robot[i].y = 0;
    }
}

bool CanGo(Point from, Point to)
{
    return (from.x <= to.x && from.y <= to.y);
}

Point MakePoint(lld a, lld b)
{
    Point ret;

    ret.x = a;
    ret.y = b;

    return ret;
}

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

    lld i,j,ii,jj,ind;
    lld a,b;
    lld l,r,mid, ans = 1;
    bool success;
    Point last;

    scanf("%I64d %I64d %I64d",&n,&m,&k);
    for (i=1;i<=n;i++)
    {
        scanf("%I64d %I64d",&a,&b);

        box[i].x = a;
        box[i].y = b;
    }

    l=1;
    r=n;

    while (l<=r)
    {
        mid = (l+r)/2;

        if (!CanGo(box[mid], MakePoint(m,m)))
        {
            r = mid-1;
            continue;
        }

        success = true;

        current.clear();
        svr.clear();

        for (i=1;i<=mid;i++)
        {
            current.push_back(box[i]);
        }

        sort(current.begin(),current.end(),SH);

        ind = 1;
        while (ind <= k && current.size() > 0)
        {
            svr.clear();
            last = current[0];

            for (i=1;i<current.size();i++)
            {
                if (!CanGo(last, current[i]))
                {
                    svr.push_back(current[i]);
                }
                else
                {
                    last = current[i];
                }
            }

            current = svr;
            ind++;
        }

        if (current.size() != 0)
        {
            r = mid - 1;
        }
        else
        {
            ans = mid;
            l = mid + 1;
        }
    }

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

/*
6 4 1
4 3
1 2
2 2
2 1
1 1
3 2
*/