#include <bits/stdc++.h>
#define GET_MACRO(_1,_2,_3,_4,_5,_6,NAME,...) NAME
#define pr(...) cerr<< GET_MACRO(__VA_ARGS__,pr6,pr5,pr4,pr3,pr2,pr1)(__VA_ARGS__) <<endl
#define pr1(a) (#a)<<"="<<(a)<<" "
#define pr2(a,b) pr1(a)<<pr1(b)
#define pr3(a,b,c) pr1(a)<<pr2(b,c)
#define pr4(a,b,c,d) pr1(a)<<pr3(b,c,d)
#define pr5(a,b,c,d,e) pr1(a)<<pr4(b,c,d,e)
#define pr6(a,b,c,d,e,f) pr1(a)<<pr5(b,c,d,e,f)
#define pr7(a,b,c,d,e,f,g) pr1(a)<<pr6(b,c,d,e,f,g)
#define pr8(a,b,c,d,e,f,g,h) pr1(a)<<pr7(b,c,d,e,f,g,h)
using namespace std;
using Int = long long;
using ll = long long;
using Double = long double;
const Int INF = 1LL<<55;
const Int mod = (1e9)+7;
using P = pair<Int,Int>;
using T = tuple<Int,Int,Int>;
const Double EPS = 1e-8;
const Double PI = 6.0 * asin((Double)0.5);
template<class T> T Max(T &a,T b){return a=max(a,b);}
template<class T> T Min(T &a,T b){return a=min(a,b);}
ostream& operator<<(ostream& o,P p){return o<<"("<<p.first<<","<<p.second<<")";}
ostream& operator<<(ostream& o,T t){return o<<"("<<get<0>(t)<<","<<get<1>(t)<<","<<get<2>(t)<<")";}
istream& operator>>(istream& i,P &p){return i>>p.first>>p.second;}
ostream& operator<<(ostream& o,vector<auto> &a){Int i=0;for(auto t:a)o<<(i++?" ":"")<<t;return o;}
istream& operator>>(istream& i,vector<auto> &a){for(auto &t:a)i>>t;return i;}
void prArr(auto a,string s=" "){Int i=0;for(auto t:a)cout<<(i++?s:"")<<t;cout<<endl;}

class CumulativeSum{
public:
  typedef long long ll;
  vector<Int> sum;
  CumulativeSum(){}
  CumulativeSum(vector<Int> A){
    Int n = A.size();
    sum.resize(n+1,0);
    for(Int i=1;i<=n;i++) sum[i] += sum[i-1] + A[i-1];
  }
  Int get(Int l,Int r){assert(l<=r && l>=0 && r<=(Int)sum.size());return sum[r] - sum[l];} //[l,r)
};

class RMQ{
public : 
  typedef long long ll;
  ll INF = 1LL<<55;
  struct data{
    bool type; //0 - empty   , 1 - update
    ll value;
  };
  ll n,n_;
  vector<ll> dat;
  vector<data> td;
  Int toMax; //0 -> RangeMin 1->RangeMax;
  
  RMQ(){n=-1;}
  RMQ(Int n_,Int toMax = 0):n_(n_),toMax(toMax){
    n=1;
    while(n<n_)n*=2;
    td.resize(2*n-1,(data){0,0});
    dat.resize(2*n-1,INF);
  }
  
  //[a,b)の値をxに変更　update(a,b,x)
  ll update(Int a,Int b,ll x,bool flg=true,Int k=0,Int l=0,Int r=-1){
    if(r == -1) {
      r = n;
      assert(a <= b), assert(a <= n && b <= n), assert(a >= 0 && b >= 0);
      if(toMax) x *= -1;
    }
    
    if(r<=a||b<=l)return flg? dat[k]:INF;
    if(a<=l&&r<=b){
      if(flg==true){
        td[k]=(data){1,x};
        dat[k]=x;
      }
      return dat[k];
    }
    
    if(td[k].type){
      td[k].type=0;
      dat[k*2+1] = dat[k*2+2] = td[k].value;
      td[k*2+1] = td[k*2+2] = (data){1,td[k].value};
    }
    
    ll vl=update(a,b,x,flg,k*2+1,l,(l+r)/2);
    ll vr=update(a,b,x,flg,k*2+2,(l+r)/2,r);
    if(flg==true)dat[k]=min(vl,vr);
    return min(vl,vr);
  }
  
  //[a,b)の最小値を得る　find(a,b);
  ll find(Int a,Int b){return (toMax? -1:1) * update(a,b,0,false);};

};



signed main(){
  cin.tie(0);
  ios_base::sync_with_stdio(0);
  cout << fixed << setprecision(12);
  
  Int n;
  cin>>n;
  vector<Int> B(n);
  cin>>B;
  
  Int m;
  cin>>m;
  vector<P> A(m);
  cin>>A;
  for(auto &a:A) a.first--;
  sort(A.begin(), A.end());
  
  CumulativeSum sum(B);
  
  RMQ dp(n + 10, 1);
  dp.update(0, 1, 0);
  
  Int p = 0;
  auto update0=[&](Int i){
    Int a = dp.find(i+1, i+2);
    Int b = (dp.find(i, i+1) + sum.get(0, i))  + (B[i] == 0) - ( sum.get(0,i+1) );
    if(a < b) dp.update(i+1, i+2, b);
  };

  auto update1=[&](Int l,Int r){ //[l,r)
    Int a = dp.find(r, r+1);
    Int b = dp.find(l, r);
    if(a < b) dp.update(r, r+1, b);
  };
  

  for(Int i=0;i<m;i++){
    Int l, r; tie(l, r) = A[i];
    while(p < l) update0(p++);
    update1(l, r);
  }
  while(p < n) update0(p++);
  
  Int ans = n - ( dp.find(n, n+1) + sum.get(0 , n) );
  cout<<ans<<endl;
  
  return 0;
}


Measured memory_bytes: 18788