#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(int i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...) cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...) {}
#endif

vector<vector<int>> tree;
int sz;

void add(int w, int a, int b, int l, int r, int val) {
	if (a > r or b < l)
		return;
	if (a >= l and b <= r) {
		tree[w].emplace_back(val);
		if (ssize(tree[w]) > 3) {
			sort(tree[w].rbegin(), tree[w].rend());
			tree[w].pop_back();
		}
		return;
	}
	const int mid = (a + b) / 2;
	add(w * 2, a, mid, l, r, val);
	add(w * 2 + 1, mid + 1, b, l, r, val);
}
int que(int pos) {
	pos += sz;
	vector<int> ret;
	while (pos) {
		ret.insert(ret.end(), tree[pos].begin(), tree[pos].end());
		pos /= 2;
	}
	sort(ret.rbegin(), ret.rend());
	ret.resize(3);
	int ans = accumulate(ret.begin(), ret.end(), 0);
	return ans;
}

int main() {
	cin.tie(0)->sync_with_stdio(0);

	int t;
	cin >> t;
	REP(tt, t) {
		tree.clear();

		int n;
		cin >> n;

		sz = 1;
		while (sz < n)
			sz *= 2;

		tree.resize(2 * sz);

		vector<int> r(n), s(n);
		REP(i, n)
			cin >> r[i] >> s[i];
		debug(n, r, s);

		REP(i, n) {
			int L = max(0, i - r[i]);
			int R = min(n - 1, i + r[i]);
			add(1, 0, sz - 1, L, R, s[i]);
		}
		int answer = 0;
		REP(i, n) {
			answer = max(answer, que(i));
		}
		cout << answer << '\n';
	}
}