Q2

#include <bits/stdc++.h>
typedef int_fast64_t lli;
using namespace std;

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    lli a, n, m;
    cin >> a >> n >> m;
    map<string, map<string, lli> > mp1;
    map<string, map<string, lli> > mp2;
    for(lli i = 0; i < n; i++)
    {
        lli w;
        string s1, s2;
        cin >> s1 >> s2 >> w;
        mp1[s1][s2] = w+1;
    }
    mp2 = mp1;
    for(lli i = 0; i < m; i++)
    {
        lli w;
        string s1, s2;
        cin >> s1 >> s2 >> w;
        mp2[s1][s2] = w+1;
    }

    lli ans = 0;
    for(auto x : mp1)
    {
        for(auto y : x.second)
        {
            lli cost = y.second - 1;
            lli mn = 1e10;

            for(auto xx : mp2[x.first])
            {
                if(xx.first == y.first)
                {
                    mn = min(mn, xx.second - 1);
                }
                else if(mp2[xx.first][y.first] != 0)
                {
                    mn = min(mn, xx.second + mp2[xx.first][y.first] - 2);
                }
            }

            //cout << mn << endl;
            ans += cost-mn;
        }
    }

    cout << ans << '\n';
    return 0;
}