这道题

窝代码是

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

//#define Fread

#ifdef Fread
char buf[1 << 21], *iS, *iT;
#define gc() (iS == iT ? (iT = (iS = buf) + fread (buf, 1, 1 << 21, stdin), (iS == iT ? EOF : *iS ++)) : *iS ++)
#endif // Fread

template <typename T>
void r1(T &x) {
	x = 0;
	char c(getchar());
	int f(1);
	for(; c < '0' || c > '9'; c = getchar()) if(c == '-') f = -1;
	for(; '0' <= c && c <= '9';c = getchar()) x = (x * 10) + (c ^ 48);
	x *= f;
}

template <typename T,typename... Args> inline void r1(T& t, Args&... args) {
    r1(t);  r1(args...);
}

const int maxn = 4e5 + 5;

#define int long long
int n[10], m;
int a[10][maxn];
#define mp make_pair
map<pair<int, int> , int> vis;

int f[10][maxn];

struct Node {
    int id, val;
    int operator < (const Node &z) const {
        return val == z.val ? id < z.id : val < z.val;
    }
};

set<Node> q;

const int inf = 2e9;

signed main() {
//    freopen(".in", "r", stdin);
//    freopen(".out", "w", stdout);
	int i, j;
	int mx(0);
    for(i = 1; i <= 4; ++ i) r1(n[i]), mx = max(mx, n[i]);
    for(i = 1; i <= 4; ++ i) {
        for(j = 1; j <= n[i]; ++ j) r1(a[i][j]);
    }
    for(int z = 1; z <= 3; ++ z) {
        r1(m);
        for(i = 1; i <= m; ++ i) {
            int u, v;
            r1(u), r1(v);
            vis[make_pair(u + mx * (z - 1), v + mx * z)] = 1;
            vis[make_pair(v + mx * z, u + mx * (z - 1))] = 1;
        }
    }
    for(i = 1; i <= n[1]; ++ i) f[1][i] = a[1][i];
    for(i = 1; i <= n[1]; ++ i) {
        q.insert((Node) {i, f[1][i]});
    }
    for(i = 2; i <= 4; ++ i) {
        for(j = 1; j <= n[i]; ++ j) {
            int flag(0);
            for(set<Node> :: iterator it = q.begin(); it != q.end(); ++ it) {
                pair<int, int> z(make_pair(it -> id + mx * (i - 2), j + mx * (i - 1)));
                if(vis.count(z)) continue;
                else {f[i][j] = it -> val + a[i][j]; flag = 1; break;}
            }
            if(!flag) f[i][j] = inf;
        }
        q.clear();
//        q = null;
        for(j = 1; j <= n[i]; ++ j) if(f[i][j] < inf) {
            q.insert((Node) {j, f[i][j]});
        }
    }
    if(q.empty() || q.begin()->val >= inf) return puts("-1"), 0;
    printf("%lld\n", q.begin()->val);
	return 0;
}

对于 $Node$ 的重载部分，如果改成

val < z.val

就错了

求大佬帮助