我无法遍历作为地图值的向量

Question

#include<iostream>
#include<map>
#include<vector>
#include<algorithm>
using namespace std;

struct Edge{
    int dest, weight;
};

map<int, vector<Edge> > Edges;

void CreateAdj(int src){
    if(!Edges.count(src)){
        vector<Edge> temp;
        Edges[src] = temp;
    }
}
void AddEdge(int src, int dest, int weight){
    struct Edge temp;
    temp.dest = dest;
    temp.weight = weight;

    Edges[src].push_back(temp);

}
int main(){


int Edges; 
cin >> Edges;
int src, dest, weight;
for(int i = 0; i < Edges; i++){
    cin >> src >> dest >> weight;
    CreateAdj(src);
    CreateAdj(dest);
    AddEdge(src, dest, weight);
    AddEdge(dest, src, weight);
}

int x;
cin >> x;
for(vector<Edge>::iterator it = Edges[x].begin(); it!=Edges[x].end(); ++it){
        cout << it->weight;
    }    
}

I was trying to implement Dikjstra's shortest path. For the adjacency list, I created a map where int was key to a vector of the struct Edge, where Edge contains the weight and the destination.

I have actually made some changes from what I had originally written. I though the vector may not be getting initiated at all, so I added the CreateAdj function which created a vector and mapped it in Edges.

But, I'm not able to iterate through the vector of Edges.

Right now, most variables are global. The error is:

mainI.cpp:43:60: error: subscripted value is not an array, pointer, or vector

for(vector<Edge>::iterator it = Edges[x].begin(); it!=Edges[x].end(); ++it){

When I made Edges local in int, it gave nothing. No error, no output.

Answer 1

int Edges; 
cin >> Edges;
for(vector<Edge>::iterator it = Edges[x].begin(); it!=Edges[x].end(); ++it)

"Edges" is just an integer value(not any vector), so you would not be able to iterate over it. integer "Edges" in main would override the map "Edges",which is global.

Moreover, you have not defined any Vector of "Edge" called as "Edges" and you are trying( you are meant) to iterate over map "Edges" ,which is int "Edges" in main.

Please rename you variables and data structures carefully,take care of scopes.