lanqiao 1121 蓝桥公园(floyd)

00lanqiao chap/test101-1-1.cpp

@@ -0,0 +1,45 @@
+// lanqiao 1121 蓝桥公园(floyd)
+#include <bits/stdc++.h>
+using namespace std;
+#define int long long 
+const int N = 4e2+10;
+int d[N][N];
+int inf = 2e18;
+signed main(){
+  // 请在此输入您的代码
+  ios::sync_with_stdio(0), cin.tie(0),cout.tie(0);
+  int n, m, q; cin >> n >> m >> q;
+  for(int i = 1; i <= n; i++){
+    for(int j = 1; j <= n; j++){
+        d[i][j] = inf; // 全部初始化为最大值
+    }
+    d[i][i] = 0; // 到自己的距离为0
+  }
+  while(m--){
+    int u, v, w; cin >> u >> v >> w;
+    d[u][v] = min(d[u][v], w);
+    d[v][u] = min(d[v][u], w);
+  }
+  for(int k = 1; k <= n; k++){
+    for(int i = 1; i <= n; i++){
+      for(int j = 1; j <= n; j++){
+        d[i][j] = min(d[i][j], (d[i][k] + d[k][j]));
+      }
+    }
+  }
+  for(int i = 1; i <= q; i++){
+    int st, ed; cin >> st >> ed;
+    cout << ((d[st][ed] >= inf)?-1:d[st][ed]) << '\n';
+  }
+
+  return 0;
+}
+/* test samples -> 1 3 2
+3 3 3
+1 2 1
+1 3 5
+2 3 2
+1 2
+1 3
+2 3
+*/