#ifdef ONLINE_JUDGE
#include <bits/stdc++.h>
#else
#include <algorithm>
#include <bitset>
#include <list>
#include <cassert>
#include <cmath>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <iostream>
#include <map>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
#include <queue>
#endif

using namespace std;

	// lambda : [] (int a, int b) -> bool { body return }
	// string r_str = R"(raw string)"

#define mp make_pair
#define mt make_tuple
#define eb emplace_back
#define pb push_back
#define fi first
#define se second
#define LL long long
#define ULL unsigned long long
#define PI (atan(1) * 4)
#define BASE 73
#define NMAX 10000
#define NMAX2 20001
#define MOD1 1000000007
#define ALL(V) (V).begin(), (V).end()
#define ALLR(V) (V).rbegin(), (V).rend()
#define CRLINE Duxar(__LINE__);
#define SHOWME(x) cerr << __LINE__ << ": " << #x << " = " << (x) << endl;
#define ENTER putchar('\n');

int dx4[] = {-1, 0, 1, 0};
int dy4[] = {0, 1, 0, -1};

int dx8[] = {-1, -1, 0, 1, 1, 1, 0, -1};
int dy8[] = {0, 1, 1, 1, 0, -1, -1, -1};

void Duxar(int _this_line) {
#ifndef ONLINE_JUDGE
	printf("\n . . . . . . . . . . . . . Passed line - %d\n", _this_line);
#endif
}

bool AreEqual(double a, double b) {
	return (fabs(a - b) < 1e-10);
}

template <class T>
bool GetNr(T &_value) {
	T _sign = 1;
	char ch;
	_value = 0;
	while(!isdigit(ch = getchar())) {
		if (ch == -1) {
			return false;
		}
		ch == '-' ? _sign = -1 : _sign = 1 ;
	}
	do {
		_value = _value * 10 + (ch - '0');
	} while(isdigit(ch = getchar()));
	_value *= _sign;
	return true;
}

template <class T>
void PutNr(T _value, char _ch = ' ') {
	cout << _value << _ch;
}

int D, N, M;
vector <int> values, dp;
vector <vector <int> > lastp;
vector <pair <int, int> > leaves;

bool ByLast(pair <int, int> a, pair <int, int> b) {
	return a.fi < b.fi;
}


int main(){
	string fileInput = "sum";
#ifdef INFOARENA
	freopen((fileInput + ".in").c_str(), "r", stdin);
	freopen((fileInput + ".out").c_str(), "w", stdout);
#else
#ifndef ONLINE_JUDGE
	freopen("/Users/duxar/Workplace/Xcode Projects/Selectie/Selectie/input", "r", stdin);
	//	freopen("/Users/duxar/Workplace/Xcode Projects/Selectie/Selectie/result", "w", stdout);
#endif
#endif

	int i, j;
	GetNr(D); GetNr(N); GetNr(M);
	values.resize(N);
	lastp.resize(N, vector <int> (D + 1, MOD1));
	dp.resize(N, MOD1);
	leaves.resize(M);
	for (i = 0; i < N; ++i) {
		GetNr(values[i]);
	}
	for (i = 0; i < M; ++i) {
		GetNr(leaves[i].fi); GetNr(leaves[i].se);
	}
	
	sort(ALL(leaves), ByLast);
	sort(ALL(values));
	int st, en;
	for (i = 0; i < M; ++i) {
		en = lower_bound(ALL(values), leaves[i].se) - values.begin();
		if (en == M || en == -1 || values[en] > leaves[i].se) --en;
		st = lower_bound(ALL(values), leaves[i].fi) - values.begin();
		if (st > en) continue;
		if (st == 0) {
//			dp[en] = 1;
//			lastp[en] = min(lastp[en], leaves[i].se);
			lastp[en][leaves[i].se] = 1;
		}
		else {
			for (j = 1; j < leaves[i].fi; ++j) {
				if (lastp[st - 1][j]) {
					lastp[en][leaves[i].se] = min(lastp[en][leaves[i].se], lastp[st - 1][j] + 1);
//					if (dp[en] > dp[st - 1] + 1) {
//						dp[en] = dp[st - 1] + 1;
//						lastp[en] = leaves[i].se;
//					}
//					else if (dp[en] == dp[st - 1] + 1) {
//						lastp[en] = min(lastp[en], leaves[i].se);
//					}
				}
			}
		}
	}
	int ans = MOD1;
	for (i = 1; i <= D; ++i) {
		ans = min(lastp[N - 1][i], ans);
	}
	PutNr(ans, '\n');
	return 0;
}