#include <bits/stdc++.h>
#define int long long
#define x first
#define y second
#define pb push_back
void debug() {std::cerr << "\n";}
template<class T, class... OtherArgs>
void debug(T &&var, OtherArgs &&... args) {
    std::cerr << std::forward<T>(var) << " ";
    debug(std::forward<OtherArgs>(args)...);
}
#define SZ(x) (int)(x).size()
#define all(x) (x).begin(), (x).end()
using namespace std;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
using i64 = long long;
using u64 = unsigned long long;
using LD = long double;
using PII = pair<int, int>;
constexpr int N = 200010;
constexpr int P = 1e9 + 7;

struct info {
    int sum;
};

info operator + (const info &a, const info &b) {
    info c;
    
    c.sum = a.sum + b.sum;

    return c;
}

struct tag {
    int t;
};

struct Node {
    info v;
    tag t;
} tr[N << 2];

void pushup(int u) {
    tr[u].v = tr[u << 1].v + tr[u << 1 | 1].v;
}

void settag(int u, int l, int r, tag t) {
    tr[u].v.sum += (r - l + 1) * t.t;
    tr[u].t.t += t.t;
}

void pushdown(int u, int l, int r) {
    if (tr[u].t.t) {
        int m = l + r >> 1;
        settag(u << 1, l, m, tr[u].t);
        settag(u << 1 | 1, m + 1, r, tr[u].t);
        tr[u].t = {0};
    }
}

void build(int u, int l, int r) {
    tr[u].t = {0};
    if (l == r) return tr[u].v = {0}, void();
    int m = l + r >> 1;
    build(u << 1, l, m), build(u << 1 | 1, m + 1, r);
    pushup(u);
}

void modify(int u, int l, int r, int x, int y, tag v) {
    if (x <= l && r <= y) return settag(u, l, r, v);
    int m = l + r >> 1;
    pushdown(u, l, r);
    if (x <= m) modify(u << 1, l, m, x, y, v);
    if (y > m) modify(u << 1 | 1, m + 1, r, x, y, v);
    pushup(u);
}

info query(int u, int l, int r, int x, int y) {
    if (x <= l && r <= y) return tr[u].v;
    int m = l + r >> 1;
    pushdown(u, l, r);
    if (x > m) return query(u << 1 | 1, m + 1, r, x, y);
    if (y <= m) return query(u << 1, l, m, x, y);
    return query(u << 1, l, m, x, y) + query(u << 1 | 1, m + 1, r, x, y);
}

void solve() {
    int n, m;
    cin >> n >> m;
    vector<int> a(n);
    int tot = 0;
    for (int i = 0; i < n; i++) {
        cin >> a[i];
        tot += a[i];
    }
    vector<PII> xt(m);
    for (int i = 0; i < m; i++) {
        auto &[x, t] = xt[i];
        cin >> x >> t;
        t--;
    }

    int ans = 0, lst = 0, add = 0;
    build(1, 0, n - 1);
    for (int i = 0; i < m; i++) {
        auto &[x, t] = xt[i];

        if (tot < x - lst) {
            ans = lst + tot;
            tot = 0;
            break;
        }
        modify(1, 0, n - 1, 0, n - 1, {x - lst});
        // add += x - lst;
        int add = query(1, 0, n - 1, t, t).sum;
        tot += min(add, a[t]) - (x - lst);
        modify(1, 0, n - 1, 0, n - 1, {-min(add, a[t])});
        add = query(1, 0, n - 1, t, t).sum;
        modify(1, 0, n - 1, t, t, {-add}); 
        // add -= min(add, a[t]);

        // debug("?", tot, query(1, 0, n - 1, t, t).sum);
        lst = ans = x;
    }
    // debug("?", ans, tot);
    ans += tot;
    cout << ans << '\n';
}

signed main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout << fixed << setprecision(20);
    int _ = 1;
    cin >> _;
    while (_--) {
        solve();
    }
}