#include<bits/stdc++.h>
using namespace std;
#define REP(i,st,ed) for(int i=(int)(st),i##end=(int)(ed);i<=i##end;++i)
#define DREP(i,st,ed) for(int i=(int)(st),i##end=(int)(ed);i>=i##end;--i)
template<typename T>bool chkmin(T &x,const T &y){return x>y?x=y,1:0;}
template<typename T>bool chkmax(T &x,const T &y){return x<y?x=y,1:0;}
template<typename T>T read(){
	T x=0,f=1;
	char c=getchar();
	while((c<'0')||(c>'9')){if(c=='-')f=-1;c=getchar();}
	while((c>='0')&&(c<='9'))x=(x<<1)+(x<<3)+(c^48),c=getchar();
	return x*f;
}
#define read() read<int>()
template<typename T>void write(T x,char c){
	static char t[25];
	static int tlen;
	t[tlen=1]=c;
	if(x<0)putchar('-'),x=-x;
	do t[++tlen]=(x%10)^48;
	while(x/=10);
	while(tlen)putchar(t[tlen--]);
}
const int maxn=200005;
int n,m;
int a[maxn],dp[maxn];
vector<int>g[maxn];
struct seg_tree{
	int Min[maxn<<2];
	void update(int p,int l,int r,int L,int R,int x){
		if((L<=l)&&(R>=r)){chkmin(Min[p],x);return;}
		int mid=(l+r)>>1,u=p<<1,v=u+1;
		if(L<=mid)update(u,l,mid,L,R,x);
		if(R>mid)update(v,mid+1,r,L,R,x);
	}
	int query(int p,int l,int r,int pos){
		if(l==r)return Min[p];
		int mid=(l+r)>>1,u=p<<1,v=u+1,res=Min[p];
		if(pos<=mid)chkmin(res,query(u,l,mid,pos));
		else chkmin(res,query(v,mid+1,r,pos));
		return res;
	}
}T;
int main(){
	n=read();
	REP(i,1,n)a[i]=a[i-1]+(read()^1);
	m=read();
	REP(i,1,m){
		int l=read(),r=read();
		g[r].push_back(l-1);
	}
	memset(T.Min,0x3f,sizeof(T.Min));
	memset(dp,0x3f,sizeof(dp));
	dp[0]=0;
	REP(i,1,n){
		dp[i]=dp[i-1]+(a[i]-a[i-1]==0);
		REP(j,0,g[i].size()-1){
			int tmp=min(dp[g[i][j]]-a[g[i][j]],T.query(1,0,n,g[i][j]));
//			cout<<i<<' '<<g[i][j]<<' '<<tmp+a[i]<<' '<<endl;
			chkmin(dp[i],tmp+a[i]);
			T.update(1,0,n,g[i][j]+1,i,tmp);
		}
//		cout<<i<<' '<<dp[i]<<endl;
	}
//	REP(i,1,n)
//		write(dp[i],i==n?'\n':'\n');
	write(dp[n],'\n');
	return 0;
}