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Getting a sum of these numbers [c++]

EZX (31)
How can i calculate the SUM of all these numbers that show up? the numbers are from 1-100 which can be divided by 3 but at the same time CANNOT be divided by 2.

SO its 3,9,15,21 and so on

Here is the code:

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#include <iostream.h>
#include "math.h"
#include <conio.h>
int main()
{
clrscr();
int n;
for(n=1;n<=33;n+=2) {
    cout << 3*n << endl;
}
getch();
}


Now i need to get the SUM of all these numbers so 3+9+15...
Last edited on
Owain (149)
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#include <iostream.h>
#include "math.h"
#include <conio.h>

int running_total = 0;

int main()
{
clrscr();
int n;
for(n=1;n<=33;n+=2) {
    running_total += 3*n
    cout << 3*n << endl;
}
getch();
}
Last edited on
vlad from moscow (6539)
For example it can be done the following way

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int n = 3;
int sum = 0;

while ( n < 100 && n % 2 )
{
   sum += n;
   n += 3;
}

cout << "Sum = " << sum << endl;


Or another way

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int n = 3;
int sum = 0;

while ( n < 100 )
{
   sum += n;
   n += 6;
}

cout << "Sum = " << sum << endl;

Last edited on
EZX (31)
Very quick answers, i had a thought about that ''while'' command but had no idea how to put that together,

running total is something completely new to me.

EZX (31)
works flawlessly

Thanks guys!
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