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?????????C++???

#include 
   
    #include 
    
     #include 
     
      #include 
      
       #include 
       
        using namespace std;const int inf = 1 << 30;const int maxn = 1005;const int maxm = 1e6 + 1e4;struct edge {    int to;    int w;    int h;    int next;};struct Node {    int k, s;    Node(int a, int b) {        k = a;        s = b;    }    bool operator<(const Node a) const {        return s < a.s;    }};int dijkstra(int s, int t, int x) {    int dist[s + 1];    fill(dist, dist + s + 1, inf);    dist[s] = 0;    priority_queue
        
          q; q.push(Node(s, 0)); int visited[s + 1] = {0}; while (!q.empty()) { Node p = q.top(); q.pop(); if (visited[p.k]) continue; visited[p.k] = 1; for (int i = head[p.k]; i != -1; i = e[i].next) { edge f = e[i]; if (f.h != -1 && f.h < x) continue; if (dist[f.to] > dist[p.k] + f.w) { dist[f.to] = dist[p.k] + f.w; q.push(Node(f.to, dist[f.to])); } } } return (dist[t] == inf) ? -1 : dist[t];}int main() { int t; scanf("%d", &t); while (t--) { int n, m; scanf("%d", &n); scanf("%d", &m); int height[n + 1]; for (int i = 1; i <= n; ++i) { scanf("%d", &height[i]); } edge e[maxm * 2]; int head[n + 1] = {-1}; int cnt = 0; for (int i = 0; i < m; ++i) { int x, y, z, c; scanf("%d", &x); scanf("%d", &y); scanf("%d", &z); scanf("%d", &c); addedge(x, y, z, c); addedge(y, x, z, c); } int l = 0, r = height[1] - height[n]; int max_height = -1; int max_length = 0; while (l <= r) { int mid = l + (r - l) / 2; int current_max_height = mid; int ans = dijkstra(1, n, current_max_height); if (ans != -1) { if (current_max_height > max_height) { max_height = current_max_height; max_length = ans; } l = mid + 1; } else { r = mid - 1; } } if (max_height == -1) { puts("cannot reach destination"); } else { puts("maximum height = " + to_string(max_height)); puts("length of shortest route = " + to_string(max_length)); } }}
        
       
      
     
    
   

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