Help with for loop

im trying to make a little dos app that finds the factorial of the number the user enters.

when i type in the number 7, i get 840, when i should be getting 5040.

here is my source:

Code:

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#include <iostream>
using namespace std;
int num;
void calculate();
void last();
int main()
{
cout<<"Please enter the number you wish to find the factorial of: ";
cin>> num;
calculate();
}
void calculate ()
{
        const int sent = num;
          for (int x = 1; x < sent - 1; x++){
              num = num * x;
              }
          last();
          }
void last()
      {
          int input;
          cout<<"The answer is: " << num <<" \n";
          cin.get();
          cout<<"\n Would you like to enter another number?\n\n1.)Yes\n2.)No\n\nSelection:";
          cin>> input;
          switch (input){
          case 1:
              cin.get();
              main();
              break;
          case 2:
              cout<<"Thank you for using this program. Have a nice day.\n";
              cin.get();
              break;
              }
              }

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Check the logic of your loop condition:
x < sent - 1
This will terminate if x == sent - 1, and hence, that number will not get multiplied in.

Cheers

Code:

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x < sent - 1

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Change that to either of the following:

Code:

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x <= sent - 1

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Code:

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x < sent

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Mwahaha! Beat you! :D

Adam Sandler said it best:

You're gonna die, clown!

thanks guys. :)

i had originally put that there, but changed it cause i thought it wouldnt work :p maybe i should have tested it 1st.

>>>maybe i should have tested it 1st.
Always a good idea. I've done that several times and ended up spending two hours fixing something I had right the first time.