C++ Program To Print Number Without Reassigning

Here, we will build a C++ program to print the number pattern without Reassigning using 2 approaches i.e.

1. Using for loop
2. Using while loop

1. Using for loop

Input: 

n = 5

Output:

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15  

The first for loop is used to iterate the number of rows and the second for loop is used to repeat the number of columns. Then print the number and increment the number to print the next number. 

C++

// C++ program to print number pattern
// without re assigning using for loop
#include <iostream>
using namespace std;

int main()
{

    int rows, columns, number = 1, n = 5;

    // first for loop is used to identify number of rows
    for (rows = 0; rows <= n; rows++) {

        // second for loop is used to identify number of
        // columns and here the values will be changed
        // according to the first for loop
        for (columns = 0; columns < rows; columns++) {

            // printing number pattern based on the number
            // of columns
            cout << number << " ";

            // incrementing number at each column to print
            // the next number
            number++;
        }

        // print the next line for each row
        cout << "\n";
    }
    return 0;
}

Output

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15 

2. Using while loop

Input: 

n = 5

Output:

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15  

The while loops check the condition until the condition is false. If the condition is true then it enters into the loop and executes the statements. 

C++

// C++ program to print number without
// reassigning patterns using while loop
#include <iostream>
using namespace std;

int main()
{
    int rows = 1, columns = 0, n = 5;

    // 1 value is assigned to the number
    // helpful to print the number pattern
    int number = 1;

    // while loops check the condition and repeat
    // the loop until the condition is false
    while (rows <= n) {

        while (columns <= rows - 1) {

            // printing number to get required pattern
            cout << number << " ";

            // incrementing columns value
            columns++;

            // incrementing number value to print the next
            // number
            number++;
        }
        columns = 0;

        // incrementing rows value
        rows++;
        cout << endl;
    }
    return 0;
}

Output

1 
2 3 
4 5 6 
7 8 9 10 
11 12 13 14 15