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Someone know what is wrong with my program?

closed account (4wRjE3v7)
Hi so I made a program using if statements, but when I put 64 as the input it does include all of the correct input except the last part "Not divisible!" I really don't know how to fix the problem anyone please care to look over my code and help me. I am new to c++.



#include <iostream>
using namespace std;

int main()
{
int num;
cout << "Please enter a number\n";
cin >> num;

if (num % 2 == 0)
{
cout << "Divisible by 2!\n";

}

else if (num % 3 == 0)
{
cout << "Divisible by 3!\n";

}

if (num % 4 == 0)
{
cout << "Divisible by 4!\n";
}
if (num % 5 == 0)
{
cout << "Divisible by 5!\n";
}
if (num % 6 == 0)
{
cout << "Divisible by 6!\n";

}
if (num % 7 == 0)
{
cout << "Divisible by 7!\n";

}
if (num % 8 == 0)
{
cout << "Divisible by 8!\n";
}
if (num % 9 == 0)
{
cout << "Divisible by 9!\n";
}
else
{
cout << "Sorry not divisible by anything!!\n";
}
}
joneele (78)
cuz this loop is wrong try 9 and check that out...

the scope of that else starts as below...

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....
if (num % 9 == 0)
{
cout << "Divisible by 9!\n";
}
else
{
cout << "Sorry not divisible by anything!!\n";
}
....
Last edited on
joneele (78)
How about this?

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#include <iostream>
using namespace std;

int main()
{
int num;
cout << "Please enter a number\n";
cin >> num;

for(int Ivalue = 2; Ivalue <= 9 ; ++Ivalue)
{
	if(num % Ivalue == 0)
	{
		cout << "Divisible by " << Ivalue << endl;
	}
}

return 0;
}
MikeyBoy (5631)
Firstly, when posting code, please enclose it in code tags to make it more readable.

The problem isn't really a C++ problem, it's a basic logic problem. You need to think more clearly about the logic of your if and else . For example, you have the following:

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if (num % 2 == 0)
{
  cout << "Divisible by 2!\n";
}

else if (num % 3 == 0)
{
  cout << "Divisible by 3!\n";
}

This will only check whether num is divisible by 3 if it fails the test for being divisible by 2.

What will happen if num is 6? The first test will register as true, as 6 is is divisible by 2. It will not perform the second test, so will not report that 6 is divisible by 3 as well.

The specific problem you mentioned is down to your final if and else:
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if (num % 9 == 0)
{
  cout << "Divisible by 9!\n";
}
else
{
  cout << "Sorry not divisible by anything!!\n";
}

It should be clear what's happening here - if num isn't divisible by 9, then it will report "not divisible", regardless of what other numbers it is divisible by.
Last edited on
cmc69 (5)
joneele that was awesome and fast.. i just copied it to codeblocks and it worked fine..
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