# Summation of Natural Number Sequence with c and c++.

To sum up a natural number sequence using C++ programming language, you can follow these steps:

Declare and initialize variables: Start by declaring two variables, "num" and "sum," both of type integer. Set "num" to the first number in the sequence, and set "sum" to 0.

Read the last number in the sequence: Prompt the user to enter the last number in the sequence and store it in a variable called "lastNum."

Use a loop to calculate the sum: Create a loop that runs until "num" is less than or equal to "lastNum." Inside the loop, add the value of "num" to the variable "sum" and increment "num" by 1.

Display the sum: Once the loop finishes, print the value of "sum" to the console.

Here's an example of C++ code that implements these steps:

```
#include <iostream>
int main() {
int num = 1;
int sum = 0;
int lastNum;
std::cout << "Enter the last number in the sequence: ";
std::cin >> lastNum;
while (num <= lastNum) {
sum += num;
num++;
}
std::cout << "The sum of the natural number sequence is: " << sum << std::endl;
return 0;
}
```

In this code, the user is prompted to enter the last number in the sequence. The loop then iterates from 1 to the last number, adding each number to the sum. Finally, the sum is displayed on the console.