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Test Case Generation | Set 4 (Random directed / undirected weighted and unweighted Graphs)
  • Difficulty Level : Hard
  • Last Updated : 30 May, 2018

Generating Random Directed Unweighted Graphs

  • Since this is a graph, the test data generation plan doesn’t guarantee that a cycle gets formed or not.
  • The number of edges – NUMEDGE is greater than zero and less than NUM*(NUM-1)/2, where NUM = Number of Vertices
  • For each RUN we first print the number of vertices – NUM first in a new separate line and the next NUMEDGE lines are of the form (a b) where a is connected to b and the edge is directed from a to b  (a->b)
  • Each of the NUMEDGE lines will have distinct edges, for e.g – if (1, 2) is there in one of the NUMEDGE lines then it is guaranteed, that (1, 2) will not be there in the remaining NUMEDGE-1 lines as this is a directed graph.




// A C++ Program to generate test cases for
// an unweighted directed graph
#include<bits/stdc++.h>
using namespace std;
  
// Define the number of runs for the test data
// generated
#define RUN 5
  
// Define the maximum number of vertices of the graph
#define MAX_VERTICES 20
  
// Define the maximum number of edges
#define MAX_EDGES 200
  
int main()
{
    set<pair<int, int>> container;
    set<pair<int, int>>::iterator it;
      
    // Uncomment the below line to store
    // the test data in a file
    // freopen ("Test_Cases_Directed_Unweighted_Graph.in", "w", stdout);
      
    //For random values every time
    srand(time(NULL));
      
    int NUM;    // Number of Vertices
    int NUMEDGE; // Number of Edges
      
    for (int i=1; i<=RUN; i++)
    {
        NUM = 1 + rand() % MAX_VERTICES;
      
        // Define the maximum number of edges of the graph
        // Since the most dense graph can have N*(N-1)/2 edges
        // where N =  nnumber of vertices in the graph
        NUMEDGE = 1 + rand() % MAX_EDGES;
          
        while (NUMEDGE > NUM*(NUM-1)/2)
                NUMEDGE = 1 + rand() % MAX_EDGES;        
          
        // First print the number of vertices and edges
        printf("%d %d\n", NUM, NUMEDGE);
          
        // Then print the edges of the form (a b)
        // where 'a' is connected to 'b'
        for (int j=1; j<=NUMEDGE; j++)
        {
            int a = 1 + rand() % NUM;
            int b = 1 + rand() % NUM;
            pair<int, int> p = make_pair(a, b);
              
            // Search for a random "new" edge everytime
            // Note - In a tree the edge (a, b) is same 
            // as the edge (b, a)
            while (container.find(p) != container.end())
            {
                a = 1 + rand() % NUM;
                b = 1 + rand() % NUM;
                p = make_pair(a, b);
            }
            container.insert(p);
        }
              
        for (it=container.begin(); it!=container.end(); ++it)
            printf("%d %d\n", it->first, it->second);
              
        container.clear();
        printf("\n");            
      
    }
    // Uncomment the below line to store
    // the test data in a file
    // fclose(stdout);
    return(0);
}

Generating Random Directed Weighted Graphs

  • Since this is a graph, the test data generation plan doesn’t guarantee that a cycle gets formed or not.
  • The number of edges – NUMEDGE is greater than zero and less than NUM*(NUM-1)/2, where NUM = Number of Vertices
  • For each RUN we first print the number of vertices – NUM first in a new separate line and the next NUMEDGE lines are of the form (a b wt) where a is connected to b and the edge is directed from a to b (a->b) and the edge has a weight of wt
  • Each of the NUMEDGE lines will have distinct edges, for e.g – if (1, 2) is there in one of the NUMEDGE lines then it is guaranteed, that (1, 2) will not be there in the remaining NUMEDGE-1 lines as this is a directed graph.




// A C++ Program to generate test cases for
// a weighted directed graph
#include<bits/stdc++.h>
using namespace std;
  
// Define the number of runs for the test data
// generated
#define RUN 5
  
// Define the maximum number of vertices of the graph
#define MAX_VERTICES 20
  
// Define the maximum number of edges
#define MAX_EDGES 200
  
// Define the maximum weight of edges
#define MAXWEIGHT 200
  
int main()
{
    set<pair<int, int>> container;
    set<pair<int, int>>::iterator it;
  
    // Uncomment the below line to store
    // the test data in a file
    // freopen("Test_Cases_Directed_Weighted_Graph.in",
    //          "w", stdout);
  
    // For random values every time
    srand(time(NULL));
  
    int NUM;    // Number of Vertices
    int NUMEDGE; // Number of Edges
  
    for (int i=1; i<=RUN; i++)
    {
        NUM = 1 + rand() % MAX_VERTICES;
  
        // Define the maximum number of edges of the graph
        // Since the most dense graph can have N*(N-1)/2 edges
        // where N =  n number of vertices in the graph
        NUMEDGE = 1 + rand() % MAX_EDGES;
  
        while (NUMEDGE > NUM*(NUM-1)/2)
            NUMEDGE = 1 + rand() % MAX_EDGES;
  
        // First print the number of vertices and edges
        printf("%d %d\n", NUM, NUMEDGE);
  
        // Then print the edges of the form (a b)
        // where 'a' is connected to 'b'
        for (int j=1; j<=NUMEDGE; j++)
        {
            int a = 1 + rand() % NUM;
            int b = 1 + rand() % NUM;
            pair<int, int> p = make_pair(a, b);
  
            // Search for a random "new" edge every time
            // Note - In a tree the edge (a, b) is same
            // as the edge (b, a)
            while (container.find(p) != container.end())
            {
                a = 1 + rand() % NUM;
                b = 1 + rand() % NUM;
                p = make_pair(a, b);
            }
            container.insert(p);
        }
  
        for (it=container.begin(); it!=container.end(); ++it)
        {
            int wt = 1 + rand() % MAXWEIGHT;
            printf("%d %d %d\n", it->first, it->second, wt);
        }
  
        container.clear();
        printf("\n");
  
    }
  
    // Uncomment the below line to store
    // the test data in a file
    // fclose(stdout);
    return(0);
}

Generating Random Undirected Unweighted Graphs

  • Since this is a graph, the test data generation plan doesn’t guarantee that a cycle gets formed or not.
  • The number of edges – NUMEDGE is greater than zero and less than NUM*(NUM-1)/2, where NUM = Number of Vertices
  • For each RUN we first print the number of vertices – NUM first in a new separate line and the next NUMEDGE lines are of the form (a b) where a is connected to b
  • Each of the NUMEDGE lines will have distinct edges, for e.g – if (1, 2) is there in one of the NUMEDGE lines then it is guaranteed, that (1, 2) and (2, 1) both will not be there in the remaining NUMEDGE-1 lines as this is an undirected graph.




// A C++ Program to generate test cases for
// an unweighted undirected graph
#include<bits/stdc++.h>
using namespace std;
  
// Define the number of runs for the test data
// generated
#define RUN 5
  
// Define the maximum number of vertices of the graph
#define MAX_VERTICES 20
  
// Define the maximum number of edges
#define MAX_EDGES 200
  
int main()
{
    set<pair<int, int>> container;
    set<pair<int, int>>::iterator it;
  
    // Uncomment the below line to store
    // the test data in a file
    // freopen("Test_Cases_Undirected_Unweighted_Graph.in",
    //         "w", stdout);
  
    // For random values every time
    srand(time(NULL));
  
    int NUM;    // Number of Vertices
    int NUMEDGE; // Number of Edges
  
    for (int i=1; i<=RUN; i++)
    {
        NUM = 1 + rand() % MAX_VERTICES;
  
        // Define the maximum number of edges of the graph
        // Since the most dense graph can have N*(N-1)/2 edges
        // where N =  nnumber of vertices in the graph
        NUMEDGE = 1 + rand() % MAX_EDGES;
  
        while (NUMEDGE > NUM*(NUM-1)/2)
            NUMEDGE = 1 + rand() % MAX_EDGES;
  
        // First print the number of vertices and edges
        printf("%d %d\n", NUM, NUMEDGE);
  
        // Then print the edges of the form (a b)
        // where 'a' is connected to 'b'
        for (int j=1; j<=NUMEDGE; j++)
        {
            int a = rand() % NUM;
            int b = rand() % NUM;
            pair<int, int> p = make_pair(a, b);
            pair<int, int> reverse_p = make_pair(b, a);
  
            // Search for a random "new" edge everytime
            // Note - In a tree the edge (a, b) is same
            // as the edge (b, a)
            while (container.find(p) != container.end() ||
                    container.find(reverse_p) != container.end())
            {
                a = rand() % NUM;
                b = rand() % NUM;
                p = make_pair(a, b);
                reverse_p = make_pair(b, a);
            }
            container.insert(p);
        }
  
        for (it=container.begin(); it!=container.end(); ++it)
            printf("%d %d\n", it->first, it->second);
  
        container.clear();
        printf("\n");
  
    }
  
    // Uncomment the below line to store
    // the test data in a file
    // fclose(stdout);
    return(0);
}

Generating Random Undirected Weighted Graphs

    • Since this is a graph, the test data generation plan doesn’t guarantee that a cycle gets formed or not.
    • The number of edges – NUMEDGE is greater than zero and less than NUM*(NUM-1)/2, where NUM = Number of Vertices
    • For each RUN we first print the number of vertices – NUM first in a new separate line and the next NUMEDGE lines are of the form (a b wt) where a is connected to b and the edge has a weight of wt
    • Each of the NUMEDGE lines will have distinct edges, for e.g – if (1, 2) is there in one of the NUMEDGE lines then it is guaranteed, that (1, 2) and (2, 1) both will not be there in the remaining NUMEDGE-1 lines as this is an undirected graph.




// A C++ Program to generate test cases for
// an weighted undirected graph
#include<bits/stdc++.h>
using namespace std;
  
// Define the number of runs for the test data
// generated
#define RUN 5
  
// Define the maximum number of vertices of the graph
#define MAX_VERTICES 20
  
// Define the maximum number of edges
#define MAX_EDGES 200
  
// Define the maximum weight of edges
#define MAXWEIGHT 200
  
int main()
{
    set<pair<int, int>> container;
    set<pair<int, int>>::iterator it;
  
    // Uncomment the below line to store
    // the test data in a file
    // freopen("Test_Cases_Undirected_Weighted_Graph.in",
    //          "w", stdout);
  
    //For random values every time
    srand(time(NULL));
  
    int NUM;    // Number of Vertices
    int NUMEDGE; // Number of Edges
  
    for (int i=1; i<=RUN; i++)
    {
        NUM = 1 + rand() % MAX_VERTICES;
  
        // Define the maximum number of edges of the graph
        // Since the most dense graph can have N*(N-1)/2 edges
        // where N =  nnumber of vertices in the graph
        NUMEDGE = 1 + rand() % MAX_EDGES;
  
        while (NUMEDGE > NUM*(NUM-1)/2)
            NUMEDGE = 1 + rand() % MAX_EDGES;
  
        // First print the number of vertices and edges
        printf("%d %d\n", NUM, NUMEDGE);
  
        // Then print the edges of the form (a b)
        // where 'a' is connected to 'b'
        for (int j=1; j<=NUMEDGE; j++)
        {
            int a = rand() % NUM;
            int b = rand() % NUM;
            pair<int, int> p = make_pair(a, b);
            pair<int, int> reverse_p = make_pair(b, a);
  
            // Search for a random "new" edge everytime
            // Note - In a tree the edge (a, b) is same
            // as the edge (b, a)
            while (container.find(p) != container.end() ||
                    container.find(reverse_p) != container.end())
            {
                a = rand() % NUM;
                b = rand() % NUM;
                p = make_pair(a, b);
                reverse_p = make_pair(b, a);
            }
            container.insert(p);
        }
  
        for (it=container.begin(); it!=container.end(); ++it)
        {
            int wt = 1 + rand() % MAXWEIGHT;
            printf("%d %d %d\n", it->first, it->second, wt);
        }
  
        container.clear();
        printf("\n");
  
    }
  
    // Uncomment the below line to store
    // the test data in a file
    // fclose(stdout);
    return(0);
}

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