2477 a dfs problem but need to pay attention to optimize

2477-20231205-pass/main.cpp

@@ -0,0 +1,55 @@
+#include<stdcpp.h>
+using namespace std;
+class Solution{
+public:
+    int people_counter(
+        vector<vector<int> > nodes, int k, int prev, long long & ans, int seats
+    ){
+        int people = 1;
+        for(int node : nodes[k]){
+            if(node == prev){continue;}
+            people+=people_counter(nodes,node,k, ans, seats);
+        }
+        if(k > 0)
+            ans += (people+seats - 1)/seats;
+        return people;
+    }
+    long long minimumFuelCost(vector<vector<int> >& roads, int seats){
+        vector<vector<int> >nodes(roads.size() + 1); 
+        for(vector<int> edge: roads){
+            const int u = edge[0], v = edge[1];
+            nodes[u].push_back(v);
+            nodes[v].push_back(u);
+        }
+        long long ans = 0;
+        people_counter(nodes,0, -1, ans, seats);
+        cout<<ans<<endl;
+        return ans;
+    }
+};
+
+int main(){
+    Solution sol;
+    vector<int> rd1 = {3,1};
+    vector<int> rd2 = {3,2};
+    vector<int> rd3 = {1,0};
+    vector<int> rd4 = {0,4};
+    vector<int> rd5 = {0,5};
+    vector<int> rd6 = {4,6};
+    vector<vector<int> >ex1 = {rd1,rd2,rd3,rd4,rd5,rd6};
+    sol.minimumFuelCost(ex1, 2);
+
+    rd1[0]=0; rd1[1] = 1;
+    rd2[0]=0; rd2[1] = 2;
+    rd3[0]=0; rd3[1] = 3;
+    vector<vector<int> >ex2 = {rd1,rd2,rd3};
+
+    sol.minimumFuelCost(ex2, 5);
+
+    vector<vector<int> >ex3 ;
+    sol.minimumFuelCost(ex3,1);
+
+
+
+    
+}