#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
struct node
{
    int x;
    int y;
    int flag;
    int len;
}a[N];
int l[N];
int n,m,ans=0;
bool cmp(node a,node b)
{
    if((a.x<=b.x && a.y<b.y) || (a.x>b.x && a.x+a.len<=b.y))
    {
        return true;
    }
    else if(a.x>b.x && a.x+a.len>b.y)
    {
        return false;
    }
    else
    {
        return false;
    }
}
bool check(int z);
int main()
{
    freopen("bg.in","r",stdin);
    freopen("bg.out","w",stdout);
    cin>>n>>m;
    for(int i=1;i<=n;++i)
    {
        scanf("%d",&l[i]);
    }
    for(int i=1;i<=m;++i)
    {
        scanf("%d%d",&a[i].x,&a[i].y);
        a[i].flag=0;
        a[i].len=a[i].y-a[i].x;
    }
    sort(l+1,l+n+1);
    sort(a+1,a+m+1,cmp);
    for(int i=1;i<=n;++i)
    {
        for(int j=1;j<=m;++j)
        {
            if(l[i]>=a[j].x && l[i]<=a[j].y && a[j].flag==0)
            {
                a[j].flag=1;
                ans++;
                break;
            }
        }
    }
    cout<<ans;
    return 0;
}