#include <cstdio>
#include <vector>
#include <algorithm>
#define pb push_back
using namespace std;
const int DIM=100000,NMAX=200003;
char buff[DIM];
int poz=DIM-1;
void citeste(int &a)
{
    a=0;
    while(!('0'<=buff[poz]&&buff[poz]<='9'))
    {
        if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0;
    }
    while('0'<=buff[poz]&&buff[poz]<='9')
    {
        a=a*10 + (buff[poz]-'0');
        if(++poz==DIM) fread(buff,1,DIM,stdin),poz=0;
    }
}
int v[NMAX],st[NMAX];
long long dyn[NMAX],aint[NMAX];
int prt[NMAX],x[NMAX];
int n,m;
struct str
{
    int first;
    int second;
    bool operator <(const str &aux) const
    {
        if(first!=aux.first) return (first < aux.first);
        return second>aux.second;
    }
}evr[NMAX];
int comp(const int &a,const int &b)
{
    if(v[a]==v[b]) return st[a]>st[b];
    return v[a]<v[b];
}
void update(int p, long long value) {
    for (aint[p += n] = value; p > 1; p >>= 1)
        aint[p>>1] = max(aint[p], aint[p ^ 1]);
}

long long query(int l, int r) {
  long long res = 0;
  for (l += n, r += n; l < r; l >>= 1, r >>= 1) {
    if (l & 1)
        res = max(res, aint[l ++]);
    if (r & 1)
        res = max(res, aint[-- r]);
  }
  return res;
}
inline void citire()
{
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
    {
        st[i]=NMAX;
        scanf("%d",&v[i]);
        x[i]=i;
    }
    scanf("%d",&m);
    for(int i=1;i<=m;i++)
    {
        scanf("%d%d",&evr[i].first,&evr[i].second);
    }
}
inline void build_st()
{
    sort(evr+1,evr+m+1);
    for(int i=1;i<=m;i++)
    {
        int sc=evr[i].second,fr=evr[i].first;
        for(int j=sc;j>=fr;--j)
        {
            if(st[j]<fr-1) break;
            st[j]=fr-1;
        }
    }
}
inline void start_dyn()
{
    long long val=0;
    long long maxim=0;
    sort(x+1,x+n+1,comp);
    for(int i=1;i<=n;i++)
    {
        val=query(0,st[x[i]]);
        dyn[x[i]]=val+v[x[i]];
        update(x[i]-1,dyn[x[i]]);
        if(maxim<dyn[x[i]]) maxim=dyn[x[i]];
    }
    if(maxim==0) while(1);
    printf("%lld\n",maxim);
}
int main()
{
    freopen("hapsan.in","r",stdin);
    freopen ("hapsan.out","w",stdout);
    citire();
    build_st();
    start_dyn();
}