C++ Program to Generate Multiplication Table

In this article, we will show you how to write a C++ program to generate the multiplication table of a number. A multiplication table shows how a number is multiplied by 1 to 10 and helps define the multiplication operation for that number. Each row displays the result of multiplying the number by values from 1 to 10.

For example, the multiplication table of 4 looks like this:

4 * 1 = 4  
4 * 2 = 8  
4 * 3 = 12  
4 * 4 = 16  
4 * 5 = 20  
4 * 6 = 24  
4 * 7 = 28  
4 * 8 = 32  
4 * 9 = 36  
4 * 10 = 40

In C++, we can generate a multiplication table using different methods. Here are the approaches we'll cover.

• Using a For Loop
• Using a While Loop
• Using a do-While Loop
• Using a Function
• Generating Table for Multiple Numbers(1 to N)

Generate Multiplication Table Using for Loop

In this approach, we use a for loop to print the multiplication table of a number. The loop goes through the numbers 1 to 10, multiplying the given number by each and printing the result.

Example

Here's the complete C++ program to generate a multiplication table using a for loop.

#include <iostream>
using namespace std;

int main() {
    int num = 2; // predefined number, for example, 4

    // Loop to print the multiplication table of 'num' from 1 to 10
    cout<<"The multiplication table for "<< num <<" is as follows:"<< endl;
    for (int i = 1; i <= 10; ++i) {
        cout << num << " * " << i << " = " << num * i << endl;
    }
    return 0;
}

The output below displays the multiplication table for the chosen number from 1 to 10.

The multiplication table for 2 is as follows:
2 * 1 = 2
2 * 2 = 4
2 * 3 = 6
2 * 4 = 8
2 * 5 = 10
2 * 6 = 12
2 * 7 = 14
2 * 8 = 16
2 * 9 = 18
2 * 10 = 20

Time Complexity:O(1) because the loop runs a fixed number of times(10).

Space Complexity: O(1) because only a few variables are used.

Generate Multiplication Table Using while Loop

In this approach, we use a while loop to print the multiplication table of a number. The loop keeps running until the counter reaches 10.

Example

Here's the complete C++ program to generate a multiplication table using a while loop.

#include <iostream>
using namespace std;

int main() {
    int num = 3;
    int i = 1;   // initialize loop counter

    cout << "The multiplication table for " << num << " is as follows:" << endl; 
    // Loop to print the multiplication table of 'num' from 1 to 10
    while (i <= 10) {
        cout << num << " * " << i << " = " << num * i << endl;
        i++; // increment the loop counter
    }
    return 0;
}

Below is the output of the above program that shows the multiplication table for 3.

The multiplication table for 3 is as follows:
3 * 1 = 3
3 * 2 = 6
3 * 3 = 9
3 * 4 = 12
3 * 5 = 15
3 * 6 = 18
3 * 7 = 21
3 * 8 = 24
3 * 9 = 27
3 * 10 = 30

Time Complexity: O(1) because the loop runs a fixed number of times(10).

Space Complexity: O(1) because only a constant amount of space is used.

Generate Multiplication Table Using do-while Loop

In this approach, we use a do-while loop to generate a multiplication table. This type of loop guarantees that the code inside it will run at least once, even if the condition is false from the start.

Example

Here's a complete C++ program that uses a do-while loop to print the multiplication table of 4. It starts at 1, prints the result, increases the counter, and repeats until it reaches 10.

#include <iostream>
using namespace std;

int main() {
    int num = 7;
    int i = 1;   // initialize loop counter

    cout << "The multiplication table for " << num << " is as follows:" << endl;
    // Do-while loop to print the multiplication table of 'num' from 1 to 10
    do {
        cout << num << " * " << i << " = " << num * i << endl;
        i++; // increment the loop counter
    } while (i <= 10); // continue loop until i is greater than 10
    return 0;
}

The below output shows the multiplication table for 7, generated using a do-while loop.

The multiplication table for 7 is as follows:
7 * 1 = 7
7 * 2 = 14
7 * 3 = 21
7 * 4 = 28
7 * 5 = 35
7 * 6 = 42
7 * 7 = 49
7 * 8 = 56
7 * 9 = 63
7 * 10 = 70

Time Complexity: O(1) because the loop runs a fixed number of times(10).

Space Complexity: O(1) because only a constant amount of space is used.

Generate Multiplication Table Using User-defined Function

In this approach, we use a separate function to handle the printing of the multiplication table. This makes the program more modular and reusable.

Example

Here's a complete C++ program where we use a seprate function to generate the multiplication table.

#include <iostream>
using namespace std;

void printTable(int num) {
    // Function to print the multiplication table of 'num' from 1 to 10
    for (int i = 1; i <= 10; ++i) {
        cout << num << " * " << i << " = " << num * i << endl; // print the multiplication
    }
}

int main() {
    int num = 9; 

    cout << "The multiplication table for " << num << " is as follows:" << endl;    printTable(num); // call function to print the table
    return 0;
}

The output below shows the multiplication table for 9, generated using a separate function.

The multiplication table for 9 is as follows:
9 * 1 = 9
9 * 2 = 18
9 * 3 = 27
9 * 4 = 36
9 * 5 = 45
9 * 6 = 54
9 * 7 = 63
9 * 8 = 72
9 * 9 = 81
9 * 10 = 90

Time Complexity: O(1).

Space Complexity: O(1).

Generate Multiplication Table from 1 to N

In this approach, we print the multiplication table for multiple numbers. The program will print the table for all numbers from 1 up to a number you specify.

Example

Below is the complete C++ program. If you input a number like 3 or 4, it will print the multiplication tables for numbers 1, 2, 3, and 4.

#include <iostream> 
using namespace std;

int main() {
    int n = 2; // predefined range for the number of tables (in this case, 2 tables)
    // Loop to generate multiplication tables for numbers from 1 to n
    for (int num = 1; num <= n; ++num) {
        cout << "Multiplication table for " << num << ":\n";  
        for (int i = 1; i <= 10; ++i) {
            cout << num << " * " << i << " = " << num * i << endl;
        }
        cout << endl;
    }
    return 0;
}

The output below shows the multiplication tables generated for numbers from 1 to n (in this example, n=2):

Multiplication table for 1:
1 * 1 = 1
1 * 2 = 2
1 * 3 = 3
...
1 * 10 = 10

Multiplication table for 2:
2 * 1 = 2
2 * 2 = 4
2 * 3 = 6
...
2 * 10 = 20

Time Complexity: O(n), where n is the number of multiplication table.

Space Complexity: O(1) because the space used does not depend on the input size. So, constant amount of space is used.