// #define DEBUGGING
#include <bits/stdc++.h>
#define endl '\n'
#define ALL(V) (V).begin(), (V).end()
#define ALLR(V) (V).rbegin(), (V).rend()
using ll = std::int64_t;
using ull = std::uint64_t;
using PLL = std::pair<ll, ll>;
using TLL = std::tuple<ll, ll, ll>;
template <typename T> using V = std::vector<T>;
template <typename T> using VV = V<V<T>>;
template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return std::max(low, std::min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { return t = clamp(t, low, high); }
namespace init__ { struct InitIO { InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } } init_io; }
#define mv_rec make_v(init, tail...)
template <typename T> T make_v(T init) { return init; }
template <typename T, typename... Tail> auto make_v(T init, size_t s, Tail... tail) { return V<decltype(mv_rec)>(s, mv_rec); }
#undef mv_rec
using namespace std;

#ifdef DEBUGGING
#include "../../debug/debug.cpp"
#else
#define DEBUG(...) 0
#define DEBUG_SEPARATOR_LINE 0
#endif

template <typename T>
class SegmentTree {
public:
    ll size;
    vector<T> node;
    function<T(T, T)> comp;
    T identity_ele;  //comp(x, identity_ele) == x

    SegmentTree(const vector<T> &v, function<T(T, T)> comp, T identity_ele) 
        : comp(comp),
          identity_ele(identity_ele)
    {
        ll tmp = 1;
        while(tmp < v.size()) tmp = (tmp << 1);
        this->size = tmp;
        this->identity_ele = identity_ele;
        this->comp = comp;
        node = V<T>(2 * size - 1, identity_ele);
        for(ll i = 0; i < v.size(); i++) {
            node[i + size - 1] = v[i];
        }
        for(ll i = size - 2; 0 <= i; i--) {
            node[i] = comp(node[i * 2 + 1], node[i * 2 + 2]);
        }
    }

    void update(ll pos, T value) {
        pos += size - 1;
        node[pos] = value;
        while(pos > 0) {
            pos = (pos - 1) / 2;
            node[pos] = comp(node[2 * pos + 1], node[2 * pos + 2]);
        }
    }

    T query(ll a, ll b) {
        return sub_query(a, b, 0, 0, size);
    }

    T sub_query(ll a, ll b, ll k, ll l, ll r) {
        if(r <= a || b <= l) {
            return identity_ele;
        } else if(a <= l && r <= b) {
            return node[k];
        } else {
            T left = sub_query(a, b, k * 2 + 1, l, (l + r) / 2);
            T right = sub_query(a, b, k * 2 + 2, (l + r) / 2, r);
            return comp(left, right);
        }
    }
};

const ll inf = 5e15;

int main() {
    ll N;
    cin >> N;
    V<ll> B(N);
    for (ll &e : B) cin >> e;

    SegmentTree<ll> seg(V<ll>(N + 10, inf), [](ll a, ll b) { return min(a, b); }, inf);
    seg.update(0, 0);
    ll Q;
    cin >> Q;
    V<PLL> lr(Q);
    for (auto &&e : lr) {
        ll l, r;
        cin >> l >> r;
        e = PLL(l - 1, r);
    }
    sort(ALL(lr));
    lr.emplace_back(N, N);
    
    ll cur_l = 0, ans = 0;
    for (auto &&ele : lr) {
        ll l, r;
        tie(l, r) = ele;
        while (cur_l < l) {
            ll e1 = seg.query(cur_l, cur_l + 1);
            ll e2 = seg.query(cur_l + 1, cur_l + 2);
            if (B[cur_l] == 0) {
                ans++;
                e1--;
            } else {
                e1++;
            }
            seg.update(cur_l + 1, min(e1, e2));
            cur_l++;
        }

        if (l == N) break;
        ll val = seg.query(l, r + 1);
        ll cur = seg.query(r, r + 1);
        DEBUG(make_tuple(ele, val, cur, ans));
        seg.update(r, min(val, cur));
    }

    cout << ans + seg.query(N, N + 1) << endl;
    return 0;
}


Measured memory_bytes: 14180