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C++ Exercises: Calculate the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (1+2+3+4+...+n)

C++ For Loop: Exercise-13 with Solution

Write a program in C++ to calculate the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (1+2+3+4+...+n).

Pictorial Presentation:

C++ Exercises: Calculate the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (1+2+3+4+...+n)

Sample Solution :-

C++ Code :

#include <iostream>
using namespace std;

int main()
{
    int i, j, n, sum = 0, tsum;
    cout << "\n\n Find the sum of the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (1+2+3+4+...+n):\n";
    cout << "------------------------------------------------------------------------------------------\n";
    cout << " Input the value for nth term: ";
    cin >> n;
    for (i = 1; i <= n; i++) 
	{
        tsum = 0;
        for (j = 1; j <= i; j++) 
		{
            sum += j;
            tsum += j;
            cout << j;
            if (j < i) 
			{
                cout << "+";
            }
        }
        cout << " = " << tsum << endl;
    }
    cout << " The sum of the above series is: " << sum << endl;
}

Sample Output:

 Find the sum of the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (
1+2+3+4+...+n):                                                        
-----------------------------------------------------------------------
-------------------                                                    
 Input the value for nth term: 5                                       
1 = 1                                                                  
1+2 = 3                                                                
1+2+3 = 6                                                              
1+2+3+4 = 10                                                           
1+2+3+4+5 = 15                                                         
 The sum of the above series is: 35 

Flowchart:

Flowchart: Calculate the series (1) + (1+2) + (1+2+3) + (1+2+3+4) + ... + (1+2+3+4+...+n)

C++ Code Editor:

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Previous: Write a program in C++ to calculate the sum of the series (1*1) + (2*2) + (3*3) + (4*4) + (5*5) + ... + (n*n).
Next: Write a program in C++ to find the sum of series 1 - X^2/2! + X^4/4!-.... upto nth term.

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C++ Programming: Tips of the Day

Which is faster: Stack allocation or Heap allocation

Stack allocation is much faster since all it really does is move the stack pointer. Using memory pools, you can get comparable performance out of heap allocation, but that comes with a slight added complexity and its own headaches.

Also, stack vs. heap is not only a performance consideration; it also tells you a lot about the expected lifetime of objects.

Ref : https://bit.ly/3COrdfj