Here I have given C++ program to find sum of first n natural numbers. First of all I am reading value of n and then calculating the sum using for loop.

If you have any doubts related to the program then feel free to ask in comment section.

## C++ Program to Find Sum of First n Natural Numbers

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#include<iostream> using namespace std; int main() { int i,n,sum=0; cout<<"How many numbers? "; cin>>n; for(i=1;i<=n;++i) { sum+=i; } cout<<"Sum="<<sum; return 0; } |

**Output**

How many numbers? 5

Sum=15

Dk4EvErwhat is the output ? 🙂

Neeraj Mishraoutpot will be according to input of n…………if n=3 than output will be 6

Dk4EvErok thanks last time meri exam me aaya tha par nhi bna tha 🙁

Neeraj Mishra@Dk4EvEr your welcome……………..keep visiting…………….

varun amlahey i hve seen dat some programrs do it with writing

long sum=0;

can u tell me whats that …long sum…

Neeraj Mishra@varun long is a type of datatype same as int,float etc, its range is higher than int……..sum=0 means initial value of sum is 0……..

smart smileso friend what is output?

Fatal1tyNeeraj Mishra, dude, this is old C++. I mean the turbo compiler is almost a decade old, so i suggest you start writing programs using a mordern compiler like g++,minigw,visual c++ etc..

Anonymouswhat s the use of endl plz reply?????

Neeraj Mishra@Anonymous there is no need of endl here, you can avoid it. Thanks for visiting.

arun rajan arunrajanplz help me to create a pic star using c++

vaishnavwaht is we are printing d in squar of n natural programme what is it meaning

Trupti CSum+=i ye samaj nahi aaya

Subhrajyoti MaitraPlease continue giving such programs. This one was of great help to me.

madhavis there any short cut like when we use max(a, b) we get a if a>b. similarly is there any key word in c++ like sum(a, b) then we get a+a1+a2+……+b. cause when we deal with large numbers it take lot of time to run it.

example: int n= sum(3, 8)

cout<<n

output= 33 cause 3+4+5+6+7+8= 33.