#include <bits/stdc++.h>
#define For(i, a, b) for(i32 i = (a), endi = (b); i <= endi; ++i)
#define foR(i, a, b) for(i32 i = (a), endi = (b); i >= endi; --i)
using namespace std;

template<typename T, typename U>
void chkmin(T &a, U b) { if(a > b) a = b; }

using i32 = int;
using i64 = long long;
using f64 = long double;
using pii = pair<i32, i32>;

void init() { }

void solve()
{
    i32 n, m;
    cin >> n >> m;
    vector<vector<pii>> adj(n+2);
    adj[n].emplace_back(0, 0);
    For(i, 1, n) adj[i-1].emplace_back(i, 1), adj[i].emplace_back(i-1, 1);
    For(i, 1, m)
    {
        i32 u, v, c;
        cin >> u >> v >> c;
        --u;
        adj[v].emplace_back(u, -c);
        adj[u].emplace_back(v, c);
    }
    deque<i32> q;
    vector<i32> dis(n+2, 1e9);
    dis[n] = 0;
    q.emplace_back(n);
    vector<i32> cnt(n+2);
    vector<bool> inq(n+2); inq[n] = true;
    while(!q.empty())
    {
        i32 u = q.front(); q.pop_front(); inq[u] = false;
        for(auto [v, c]: adj[u])
        {
            if(dis[v] <= dis[u] + c) continue;
            dis[v] = dis[u] + c;
            if(inq[v]) continue;
            if(!q.empty() && dis[v] > dis[q.front()]) q.push_back(v);
			else q.push_front(v);
            cnt[v]++; inq[v] = true;
			if(cnt[v] > n+2)
            { 
                cout << "?\n";
                return;
            }
        }
    }
    cout << "! ";
    For(i, 1, n)
    {
        if(dis[i] > dis[i-1]) cout << '(';
        else cout << ')';
    }
    cout << '\n';
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    init();
    i32 T = 1;
    // cin >> T;
    while(T--) solve();
    return 0;
}