#define _CRT_SECURE_NO_WARNINGS
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
ll lcm(ll a, ll b) { return 1ll * a * b / gcd(a, b); }
ll divCeil(ll x, ll y) { return x / y + (x % y != 0); }
const int MAXN = 2e5 + 5;
const double pi = 3.14159265358979323846;
const ll inf = 1e18;
double eps = 1e-9;
const int maxn = 2e5 + 5;
const int mod = 1e9 + 7;
#define endl "\n"
#define int long long
void solve() {
    int n,m;
    cin >> n >> m;
    vector<int>a(n + 5);
    vector<int>dp(m + 5);
    vector<int>x(m + 5);
    vector<int>t(m + 5);
    int sum = 0;
    for(int i = 1;i<=n;i++){
        cin >> a[i];
        sum += a[i];
    }
    for(int i = 1;i<=m;i++){
        cin >> x[i] >> t[i];
    }
    for(int i = 1;i<=m;i++){
        if(dp[i - 1] + sum >= x[i]){
            dp[i] = dp[i - 1] + min(x[i] - dp[i - 1],a[t[i]]);
        }
        else{
            cout << dp[i - 1] + sum << endl;
            return;
        }
    }
    cout << dp[m] + sum << endl;
    return;
}
signed main()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int t;
    cin >> t;
    while (t--)solve();
    return 0;
}