Test Case Generation | Set 1 (Random Numbers, Arrays and Matrices)

The test cases are an extremely important part of any “Software/Project Testing Process”. Hence this Set will be very important for all aspiring software developers. The following are the programs to generate test cases.

• Generating Random Numbers
  

C++

// A C++ Program to generate test cases for
// random number
#include<bits/stdc++.h>
using namespace std;

// Define the number of runs for the test data
// generated
#define RUN 5

// Define the range of the test data generated
#define MAX 10000000

int main()
{
    // Uncomment the below line to store
    // the test data in a file
    // freopen("Test_Cases.in", "w", stdout);

    // For random values every time
    srand(time(NULL));

    for (int i=1; i<=RUN; i++)
        printf("%d\n", rand() % MAX);

    // Uncomment the below line to store
    // the test data in a file
    //fclose(stdout);
    return(0);
}

Java

// A Java Program to generate test cases
// for random number
import java.io.*;
import java.util.Random;

class GeneratingRandomNumbers
{

    // the number of runs
    // for the test data generated
    static int requiredNumbers = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // Driver Code
    public static void main (String[] args) throws IOException
    {
        Random random = new Random();

        for(int i = 0; i < requiredNumbers; i++)
        {
            int a = random.nextInt(upperBound - lowerBound) +
                                                lowerBound;
            System.out.println(a);
        }
    }
}

// This code is contributed by Madfrost

Python3

# A Python3 Program to generate test cases
# for random number
import random

# the number of runs
# for the test data generated
requiredNumbers = 5;

# minimum range of random numbers
lowerBound = 0;

# maximum range of random numbers
upperBound = 1000;

# Driver Code
if __name__ == '__main__':

    for i in range(requiredNumbers):
        a = random.randrange(0, upperBound -
                    lowerBound) + lowerBound;
        print(a);

# This code is contributed by 29AjayKumar

C#

// A C# Program to generate test cases
// for random number
using System;

class GeneratingRandomNumbers
{

    // the number of runs
    // for the test data generated
    static int requiredNumbers = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // Driver Code
    public static void Main(String[] args)
    {
        Random random = new Random();

        for(int i = 0; i < requiredNumbers; i++)
        {
            int a = random.Next(upperBound - lowerBound) +
                                                lowerBound;
            Console.WriteLine(a);
        }
    }
}

// This code is contributed by Rajput-Ji

Javascript

<script>

let requiredNumbers = 5;
let lowerBound = 0;
let upperBound = 1000;

for(let i = 0; i < requiredNumbers; i++)
{
    let a = Math.floor(Math.random() *
    (upperBound - lowerBound)) + lowerBound;
    document.write(a+"<br>");
}


// This code is contributed by rag2127

</script>

• Generating Random Arrays
  

C++

// A C++ Program to generate test cases for
// array filled with random numbers
#include<bits/stdc++.h>
using namespace std;

// Define the number of runs for the test data
// generated
#define RUN 5

// Define the range of the test data generated
#define MAX 10000000

// Define the maximum number of array elements
#define MAXNUM 100

int main()
{
    // Uncomment the below line to store
    // the test data in a file
    //freopen ("Test_Cases_Random_Array.in", "w", stdout);

    //For random values every time
    srand(time(NULL));

    for (int i=1; i<=RUN; i++)
    {
        // Number of array elements
        int NUM = 1 + rand() % MAXNUM;

        // First print the number of array elements
        printf("%d\n", NUM);

        // Then print the array elements separated
        // by space
        for (int j=1; j<=NUM; j++)
            printf("%d ", rand() % MAX);

        printf("\n");
    }

    // Uncomment the below line to store
    // the test data in a file
    //fclose(stdout);
    return(0);
}

Java

// A Java Program to generate test cases
// for array filled with random numbers
import java.io.*;
import java.util.Random;

class GeneratingRandomArrays
{

    // the number of runs
    // for the test data generated
    static int RUN = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // minimum size of reqd array
    static int minSize = 10;

    // maximum size of reqd array
    static int maxSize = 20;

    // Driver Code
    public static void main (String[] args) throws IOException
    {
        Random random = new Random();

        for(int i = 0; i < RUN; i++)
        {
            int size = random.nextInt(maxSize - minSize) +
                                                minSize;
            int[] array = new int[size];

            System.out.println(size);

            for(int j = 0; j < size; j++)
            {
                int a = random.nextInt(upperBound - lowerBound) +
                                                    lowerBound;
                System.out.print(a + " ");
            }
            System.out.println();
        }
    }
}

// This code is contributed by Madfrost

Python3

# A Python3 Program to generate test cases
# for array filled with random numbers
import random

# the number of runs
# for the test data generated
RUN = 5;

# minimum range of random numbers
lowerBound = 0;

# maximum range of random numbers
upperBound = 1000;

# minimum size of reqd array
minSize = 10;

# maximum size of reqd array
maxSize = 20;

# Driver Code
if __name__ == '__main__':

    for i in range(RUN):
        size = random.randrange(0, maxSize - minSize) + minSize;
        array = [0]*size;

        print(size);

        for j in range(size):
            a = random.randrange(0, upperBound - lowerBound) + lowerBound;
            print(a, end=" ");

        print();


# This code is contributed by 29AjayKumar

C#

// A C# Program to generate test cases
// for array filled with random numbers
using System;

class GeneratingRandomArrays
{

    // the number of runs
    // for the test data generated
    static int RUN = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // minimum size of reqd array
    static int minSize = 10;

    // maximum size of reqd array
    static int maxSize = 20;

    // Driver Code
    public static void Main(String[] args)
    {
        Random random = new Random();

        for(int i = 0; i < RUN; i++)
        {
            int size = random.Next(maxSize - minSize) +
                        minSize;
            int[] array = new int[size];

            Console.WriteLine(size);

            for(int j = 0; j < size; j++)
            {
                int a = random.Next(upperBound - lowerBound) +
                        lowerBound;
                Console.Write(a + " ");
            }
            Console.WriteLine();
        }
    }
}

// This code is contributed by 29AjayKumar

Javascript

<script>

// A JavaScript Program to generate test cases
// for array filled with random numbers

// the number of runs
// for the test data generated
let RUN = 5;

// minimum range of random numbers
let lowerBound = 0;

// maximum range of random numbers
let upperBound = 1000;

// minimum size of reqd array
let minSize = 10;

// maximum size of reqd array
let maxSize = 20;


for(let i = 0; i < RUN; i++)
        {
            let size = Math.floor(Math.random() *
            (maxSize - minSize)) + minSize;
            let array = new Array(size);

            document.write(size+"<br>");

            for(let j = 0; j < size; j++)
            {
                let a =  Math.floor(Math.random() *
                (upperBound - lowerBound)) +
                 lowerBound;
                document.write(a + " ");
            }
            document.write("<br>");
        }


// This code is contributed by avanitrachhadiya2155

</script>

• Generating Random Matrix
  

C++

// A C++ Program to generate test cases for
// matrix filled with random numbers
#include<bits/stdc++.h>
using namespace std;

// Define the number of runs for the test data
// generated
#define RUN 3

// Define the range of the test data generated
#define MAX 100000

// Define the maximum rows in matrix
#define MAXROW 10

// Define the maximum columns in matrix
#define MAXCOL 10

int main()
{
    // Uncomment the below line to store
    // the test data in a file
    // freopen ("Test_Cases_Random_Matrix.in", "w", stdout);

    // For random values every time
    srand(time(NULL));

    for (int i=1; i<=RUN; i++)
    {
        // Number of rows and columns
        int row = 1 + rand() % MAXROW;
        int col = 1 + rand() % MAXCOL;

        // First print the number of rows and columns
        printf("%d %d\n", row, col);

        // Then print the matrix
        for (int j=1; j<=row; j++)
        {
            for (int k=1; k<=col; k++)
                printf("%d ", rand() % MAX);
            printf("\n");
        }
        printf("\n");
    }

    // Uncomment the below line to store
    // the test data in a file
    // fclose(stdout);
    return(0);
}

Java

// A Java Program to generate test cases for
// matrix filled with random numbers
import java.io.*;
import java.util.Random;

class GeneratingRandomMatrix
{
    // the number of runs
    // for the test data generated
    static int RUN = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // maximum size of column
    static int maxColumn = 10;

    // minimum size of column
    static int minColumn = 1;

    // minimum size of row
    static int minRow = 1;

    // maximum size of row
    static int maxRow = 10;

    // Driver Code
    public static void main (String[] args) throws IOException
    {
        Random random = new Random();

        for(int i = 0; i < RUN; i++)
        {
            int row = random.nextInt(maxRow - minRow) +
                                              minRow;
            int column = random.nextInt(maxColumn - minColumn) +
                                                    minColumn;

            int[][] matrix = new int[row][column];

            System.out.println(row + " " + column);

            for(int j = 0; j < row; j++)
            {
                for(int k = 0; k < column; k++)
                {
                    int a = random.nextInt(upperBound - lowerBound) +
                                                        lowerBound;
                    System.out.print(a + " ");
                }
                System.out.println();
            }
            System.out.println();
        }
    }
}

// This code is contributed by Madfrost

Python3

# A Python3 Program to generate test cases
# for matrix filled with random numbers
import random

# the number of runs
# for the test data generated
RUN = 5;

# minimum range of random numbers
lowerBound = 0;

# maximum range of random numbers
upperBound = 1000;

# maximum size of column
maxColumn = 10;

# minimum size of column
minColumn = 1;

# minimum size of row
minRow = 1;

# maximum size of row
maxRow = 10;

# Driver Code
if __name__ == '__main__':

    for i in range(RUN):
        row = random.randrange(0, maxRow - minRow) + minRow

        column = random.randrange(0, maxColumn - minColumn) + minColumn

        matrix = [[0 for i in range(column)] for j in range(row)]

        print(row, column)

        for j in range(row):
            for k in range(column):
                a = random.randrange(0, upperBound - lowerBound) +  lowerBound
                print(a ,end = " ")
            print()
        print()

# This code is contributed by Shubham Singh

C#

// A C# Program to generate test cases for
// matrix filled with random numbers
using System;

public class GeneratingRandomMatrix
{
    // the number of runs
    // for the test data generated
    static int RUN = 5;

    // minimum range of random numbers
    static int lowerBound = 0;

    // maximum range of random numbers
    static int upperBound = 1000;

    // maximum size of column
    static int maxColumn = 10;

    // minimum size of column
    static int minColumn = 1;

    // minimum size of row
    static int minRow = 1;

    // maximum size of row
    static int maxRow = 10;

    // Driver Code
    public static void Main(String[] args)
    {
        Random random = new Random();

        for(int i = 0; i < RUN; i++)
        {
            int row = random.Next(maxRow - minRow) +
                                            minRow;
            int column = random.Next(maxColumn - minColumn) +
                                                    minColumn;

            int[,] matrix = new int[row, column];

            Console.WriteLine(row + " " + column);

            for(int j = 0; j < row; j++)
            {
                for(int k = 0; k < column; k++)
                {
                    int a = random.Next(upperBound - lowerBound) +
                                                        lowerBound;
                    Console.Write(a + " ");
                }
                Console.WriteLine();
            }
            Console.WriteLine();
        }
    }
}

// This code is contributed by 29AjayKumar

Library Functions Used

1. rand() Function– 
   -> Generate random numbers from the range 0 to RAND_MAX (32767) 
   -> Defined in <stdlib.h>/<cstdlib> header 
   -> If we want to assign a random number in the range – m to n [n >= m] to a variable var, then use-
   var = m + ( rand() % ( n – m + 1 ) ); 
   -> This function is a run-time function. So the values – n, m must be declared before compiling just like we have to declare the size of array before compiling. 
   -> Call this function every time you want to generate a random number
2. time() Function
   -> Return the number of seconds from [00:00:00 UTC, January 1, 1970] 
   -> Defined in <time.h> header
3. srand(seed)
   -> Generates random number according to the seed passed to it. 
   -> If this function is not used and we use rand() function then every time we run the program the same random numbers gets generated. 
   -> To overcome the above limitation, we pass time(NULL) as a seed. Hence srand(time(NULL)) is used to generate random values every time the program is made to run. 
   -> Always use this at the beginning of the program, i.e- just after int main() { 
   -> No need to call this function every time you generate a random number 
   -> Defined in <stdlib.h>/<cstdlib> header
4. freopen(“output.txt”, “w”, stdout)
   -> Writes (that’s why we passed “w” as the second argument) all the data to output.txt file (The file must be in the same file as the program is in). 
   -> Used to redirect stdout to a file. 
   -> If the output.txt file is not created before then it gets created in the same file as the program is in.
5. fclose(stdout)
   -> Closes the standard output stream file to avoid leaks. 
   -> Always use this at the end of the program, i.e- just before return(0) in the int main() function.

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