/*

                   _ooOoo_
                  o8888888o
                  88" . "88
                  (| -_- |)
                  O\  =  /O
               ____/`---'\____
             .'  \\|     |//  `.
            /  \\|||  :  |||//  \
           /  _||||| -:- |||||-  \
           |   | \\\  -  /// |   |
           | \_|  ''\---/''  |   |
           \  .-\__  `-`  ___/-. /
         ___`. .'  /--.--\  `. . __
      ."" '<  `.___\_<|>_/___.'  >'"".
     | | :  `- \`.;`\ _ /`;.`/ - ` : | |
     \  \ `-.   \_ __\ /__ _/   .-` /  /
======`-.____`-.___\_____/___.-`____.-'======
                   `=---='
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                    prayer
*/

// g++ -std=c++11 a.cpp
#include<iostream>
#include<vector>
#include<string>
#include<algorithm>	
#include<map>
#include<set>
#include<unordered_map>
#include<utility>
#include<cmath>
#include<random>
#include<cstring>
#include<queue>
#include<stack>
#include<bitset>
#include<cstdio>
#include<sstream>
#include<iomanip>
#include<assert.h>
#include<typeinfo>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define FOR(i,a) for(auto i:a)
#define pb push_back
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)
#define show1d(v) rep(_,v.size())cout<<" "<<v[_];cout<<endl;
#define show2d(v) rep(__,v.size()){rep(_,v[__].size())cout<<" "<<v[__][_];cout<<endl;}
using namespace std;
//kaewasuretyuui
typedef long long ll;
#define int ll
typedef int Def;
typedef pair<Def,Def> pii;
typedef vector<Def> vi;
typedef vector<vi> vvi;
typedef vector<pii> vp;
typedef vector<vp> vvp;
typedef vector<string> vs;
typedef vector<double> vd;
typedef vector<vd> vvd;
typedef pair<Def,pii> pip;
typedef vector<pip>vip;
// #define mt make_tuple
// typedef tuple<int,int,int> tp;
// typedef vector<tp> vt;
template<typename A,typename B>bool cmin(A &a,const B &b){return a>b?(a=b,true):false;}
template<typename A,typename B>bool cmax(A &a,const B &b){return a<b?(a=b,true):false;}
//template<class C>constexpr int size(const C &c){return (int)c.size();}
//template<class T,size_t N> constexpr int size(const T (&xs)[N])noexcept{return (int)N;}
const double PI=acos(-1);
const double EPS=1e-9;
Def inf = sizeof(Def) == sizeof(long long) ? 2e18 : 1e9+10;
int dx[]={0,1,0,-1};
int dy[]={1,0,-1,0};

typedef int SegT;
const SegT defvalue=inf;
class SegTree{
	public:
		vector<SegT>val;
		int n;
		SegT combine(SegT a,SegT b){return min(a,b);}
		SegTree(int size){
			n=1;
			while(n<size)n<<=1;
			val=vector<SegT>(2*n,defvalue);
		}
		SegTree(const vector<SegT> &in){
			n=1;
			while(n<in.size())n<<=1;
			val=vector<SegT>(2*n,defvalue);
			for(int i=n-1+in.size()-1;i>=0;i--){
				if(n-1<=i)val[i]=in[i-(n-1)];
				else val[i]=combine(val[i*2+1],val[i*2+2]);
			}
		}
		void update(int i,SegT a){
			i+=n-1;
			val[i]=min(val[i],a);
			while(i>0){
				i=(i-1)/2;
				val[i]=combine(val[i*2+1],val[i*2+2]);
			}
		}
		SegT query(int a,int b,int k=0,int l=0,int r=-1){//[a,b)
			if(r==-1)r=n;
			if(r<=a||b<=l)return defvalue;
			if(a<=l&&r<=b)return val[k];
			else return combine(query(a,b,k*2+1,l,(l+r)/2),query(a,b,k*2+2,(l+r)/2,r));
		}
		void tmp(){
			rep(i,val.size())cout<<" "<<val[i];cout<<endl;
		}
};
signed main(){
	int n;
	cin>>n;
	vi in(n);
	rep(i,n)cin>>in[i];
	int out=0;
	rep(i,n)out+=!in[i];
	SegTree st(n+1);
	st.update(0,0);
	vvi G(n);
	int m;
	cin>>m;
	while(m--){
		int a,b;
		cin>>a>>b;
		a--;
		G[a].pb(b);
	}
	rep(i,n){
		rep(j,G[i].size()){
			st.update(G[i][j],st.query(i,G[i][j]+1));
		}
		int t=st.query(i,i+1);
		if(!in[i])t--;
		else t++;
		st.update(i+1,t);
	}
	cout<<out+st.query(n,n+1)<<endl;
}















Measured memory_bytes: 16896