矢量下标超出范围线1501

问题描述

我正在尝试从文件中读取数据，并从中制作图形。我在常规函数式编程中编写的代码很好。当我尝试将其转换为面向对象的编程方法时，它给出了错误。这是我的函数式编程代码。

struct Edge {
    int src,dest,weight;
};

vector<vector<pair<int,int>>> MakeGraph(int noOfVerticies,vector<Edge> const& edges)
{
    vector<vector<pair<int,int>>> adjList;
    adjList.resize(noOfVerticies);

    for (auto& edge : edges)
    {
        int src = edge.src;
        int dest = edge.dest;
        int weight = edge.weight;

        // insert at the end
        adjList[src].push_back(make_pair(dest,weight));
    }

    return adjList;
}

void printGraph(vector<vector<pair<int,int>>> adjList,int N)
{
    //cout << N;
    for (int i = 0; i < N; i++)
    {
        // print all neighboring vertices of given vertex
        for (pair<int,int> v : adjList[i])
            cout << "(" << i << "," << v.first <<
            "," << v.second << ") ";
        cout << endl;
    }
}

vector<vector<pair<int,int>>> readAndMakeGraph()
{
    Edge e1;
    int noOfvertices;
    bool isFirst = false;
    ifstream inFile("a1.txt");
    char ch;
    vector <Edge> v1;
    while (!inFile.eof())
    {
        if (isFirst == false)
        {
            inFile >> ch;
            noOfvertices = static_cast<int>(ch)-48;
            isFirst = true;
            //cout << noOfvertices;
        }
        else
        {
            inFile >> ch;
            e1.src = static_cast<int>(ch) - 48;
            inFile >> ch;
            e1.dest = static_cast<int>(ch) - 48;
            inFile >> ch;
            e1.weight = static_cast<int>(ch) - 48;
            v1.push_back({ e1.src,e1.dest,e1.weight });
        }
        
    }
    inFile.close();

    vector<vector<pair<int,int>>> a1 = MakeGraph(noOfvertices,v1);

    printGraph(a1,noOfvertices);
    return a1;
}

int main()
{
    vector<vector<pair<int,int>>> a1;

    a1 = readAndMakeGraph();

}

文件格式为

noOfVertices
src,weight
src,weight

现在我的面向对象代码是

Graph.cpp

#include "Graph.h"
void Graph::MakeGraph(vector<Edge> const& edges)
{
    vector<vector<pair<int,int>>> adjList;
    adjList.resize(noOfVertices);

    for (auto& edge : edges)
    {
        int src = edge.src;
        int dest = edge.dest;
        int weight = edge.weight;

        // insert at the end
        adjList[src].push_back(make_pair(dest,weight));
    }

}

void Graph::printGraph()
{
    
    for (int i = 0; i < noOfVertices; i++)
    {
        // print all neighboring vertices of given vertex
        for (pair<int,int> v : adjList[i])
            cout << "[" << i << "," << v.second << "] ";
        cout << endl;
    }
    
}

void Graph:: readAndMakeGraph()
{
    Edge e1;
    int noOfvertices;
    bool isFirst = false;
    ifstream inFile("a1.txt");
    char ch;
    vector <Edge> v1;
    while (!inFile.eof())
    {
        if (isFirst == false)
        {
            inFile >> ch;
            noOfvertices = static_cast<int>(ch) - 48;
            isFirst = true;
            //cout << noOfvertices;
        }
        else
        {
            inFile >> ch;
            e1.src = static_cast<int>(ch) - 48;
            inFile >> ch;
            e1.dest = static_cast<int>(ch) - 48;
            inFile >> ch;
            e1.weight = static_cast<int>(ch) - 48;
            v1.push_back({ e1.src,e1.weight });
        }

    }
    inFile.close();

    MakeGraph(v1);


}

Graph.h

#pragma once
#include <iostream>
#include <vector>
#include <fstream>
using namespace std;
struct Edge {
    int src,weight;
};
class Graph
{
    vector<vector<pair<int,int>>> adjList;
    int noOfVertices;
public:
    void MakeGraph(vector<Edge> const& edges);
    void printGraph();
    void readAndMakeGraph();
    
};

我的主要是

#include <iostream>
#include <vector>
#include <string>
#include <fstream>
#include "Graph.h"
using namespace std;
int main()
{
    Graph h1;
    
    h1.readAndMakeGraph();
    h1.printGraph();


}

我遇到此运行时错误。

解决方法

在函数def random_list(amount,minval,maxval,none_rate): from random import choice from numpy import linspace arr = linspace(minval,amount) none_count = round(float(amount * none_rate)) rep = [] col = [d for d in range(amount)] while none_count > 0: gen = choice(col) if gen not in rep: arr[gen] = None none_count -= 1 rep.append(gen) return arr print(random_list(10,100,0.3)) 中，定义一个函数局部变量Graph::readAndMakeGraph，它与Graph成员变量int noOfVertices 不同。稍后，当您调用Graph::noOfVertices时，它正在查看从未初始化的后者。

如果仅从该函数中删除行printGraph，它应该解决当前的问题。

int noOfVertices;中发生相同的问题，它声明了函数局部变量Graph::MakeGraph。然后，adjList看着printGraph，但从未设置。