#include<stdio.h>
#include<queue>
#include<algorithm>
using namespace std;
struct xy {
	int s, e;
}a[121212];
bool sort_s(xy a, xy b) {
	if (a.s != b.s)return a.s < b.s;
	return a.e < b.e;
}
int C[121212];
priority_queue<int>Q;
int main() {
	int n, m;
	int i, j;
	scanf("%d%d", &n, &m);
	for (i = 0; i < n; i++)scanf("%d", &C[i]);
	for (i = 0; i < m; i++)scanf("%d%d", &a[i].s, &a[i].e);
	sort(C, C + n);
	sort(a, a + m, sort_s);
	int now = 0, ans = 0;
	for (i = 0; i < n; i++) {
		while (now < m&&a[now].s <= C[i])Q.push(-a[now++].e);
		while (!Q.empty() && -Q.top() < C[i])Q.pop();
		if (!Q.empty())ans++, Q.pop();
	}
	printf("%d", ans);
	return 0;
}

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NSA0CjcKOAo2CjIKOQoyIDUKNCA5CjAgMwo4IDEz

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0 3
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