#include <iostream>
#include <cstdio>
#include <queue>
#include <algorithm>
using namespace std;
struct node
{
    int l;
    int r;
} d[100010];
int n, m, len[100010], max_len, x = 1, y = 1, ans;
deque<int> dq;
bool cmp1(node a, node b)
{
    return a.l < b.l;
}
int main()
{
    freopen("bg.in", "r", stdin);
    freopen("bg.out", "w", stdout);
    scanf("%d%d", &n, &m);
    for(int i = 1; i <= n; ++i)
        scanf("%d", &len[i]), max_len = max(len[i], max_len);
    for(int i = 1; i <= m; ++i)
        scanf("%d%d", &d[i].l, &d[i].r);
    sort(len + 1, len + n + 1); sort(d + 1, d + m + 1, cmp1);
    for(int i = 1; i <= max_len; ++i)
    {
        while(i == d[x].l)
        {
            if(!dq.empty() && d[x].r <= d[dq.front()].r) dq.push_front(x);
            else dq.push_back(x);
            ++x;
        }
        if(!dq.empty() && i == len[y] && len[y] >= d[dq.front()].l && len[y] <= d[dq.front()].r)
        {
            ++y;
            ++ans;
            dq.pop_front();
        }
        while(!dq.empty() && i == d[dq.front()].r) dq.pop_front();
    }
    printf("%d\n", ans);
    return 0;
 }