Can someone help me spot the error?

[Anonomys]

below program should display. The sum of 2 through 5 is 14 ( 2 + 3 + 4 + 5)

#include <iostream>

using namespace std;

int main ()

{
    int next = 2 , sum = 1;
    while (next <=5)
    {
        next++;
        sum = sum + next;
    }
    cout << "The sum of 2 through 5 is " << sum << endl;



    return 0;
}

[seeplus]

#include <iostream>

using namespace std;

int main() {
	int next {2}, sum {};

	while (next <= 5)
		sum += next++;

	cout << "The sum of 2 through 5 is " << sum << '\n';
}

The sum of 2 through 5 is 14

[lastchance]

@Anonomys,
in your code change:

    int next = 2 , sum = 1;
    while (next <= 5)

to

    int next = 2, sum = next;
    while (next < 5)

It would be perverse to start the sum with a value different from the starting point, and your current loop control means that you would go "one beyond" that intended (because you tested for legitimacy before you incremented).

[salem c]

Compare your result with

    while (next <=5)
    {
        sum = sum + next;
        next++;  // do this after you use next in a calculation.
    }

Then compare with

for ( next = 2 ; next <= 5 ; next++ )
{
        sum = sum + next;
}

[lastchance]

Or don't bother with a loop:

#include <iostream>
int main ()
{
   int a = 2, b = 5;
   std::cout << "The sum of " << a << " through " << b << " is " << ( b - a + 1 ) * ( a + b ) / 2 << '\n';
}

[Daathwi]

From your code ;
initialise sum to 0; ------ [line 8]
the statements in [line 11] and [line 12] must be swapped because one must first compute the value of sum and then next is incremented...

So the correct code will be

#include <iostream>
using namespace std;

int main ()

{
    int next = 2 , sum = 0;
    while (next <=5)
    {
        sum = sum + next;
        next++;
    }
    cout << "The sum of 2 through 5 is " << sum << endl;
    return 0;
}