Thread: for loop problem

I need to write a program that takes a positive integer that is input and then output an integer. the ouput is the integer input multiplied by each integer below i. e.g. if 5 was input, i need to ouput 5*4*3*2*1. I can get the number input and store it in a variable, but im not sure about the loop i need. i think it would be a 'for' loop which decreases the value of the input and then multiply that witht he value input

Post what you have, even if it's not much.

Here is all i have at the moment

Code:

#include <stdio.h>

void main(void) {

        printf("Enter a positive integer");
        scanf("%d", &num);
        fflush(stdin);

              while (num>=num && num>0) {
	     printf("%d", num*num--);
	}
}

Don't use "fflush(stdin)", search the board as to why not.

Here is a similar program i have developed unfourtunatly it still isnt working properly i seem to get 35 or somewhere there abouts by multiplyig say 5*4*3*2*1. Perhaps some one could tell me why?
[code]
#include <stdio.h>
#include <conio.h>

void main (void)
{
int num;
int x;
int mult = 0;
clrscr();

printf("please enter a number: ");
scanf("%d", &num);
fflush(stdin);

for(x=1;x<=num;x++)
{
printf("%d", x);
printf("*");
mult++;
}
x=mult*x;
printf("%d", x);


}
[\code]

I have changed the code slightly but it is still not outputting the correct value:

Code:

#include <stdio.h>
#include <conio.h>

void main(void) {
   int num;
   int x;
   int div;
     clrscr();

	printf("Enter a positive integer : ");
	scanf("%d", &num);
	fflush(stdin);

	    for (x=num; x>0; x--) {
		 printf("%d", x);
		 printf("*");
		 div++;
		 div=div*x;
		 }

	    printf(": %d", div);
	}

Code:

#include <stdio.h>


int main(int argc, char *argv[]) {
   int num=0;
   int x=0;
   int div=1;

   printf("Enter a positive integer : ");
   scanf("%d", &num);
   /* fflush(stdin); */
   
       for (x=num; x>0; x--) {
   	 printf("%d", x);
   	 if(x>1) printf("*");
   	 /* div++ */
   	 div=div*x;
   	 }   
    printf(": %d\n", div);   
   return 0;	
}

Well, obviously, you don't pick up hints very well:

Change:

1) void main(void) -> int main(void)
2) remove "fflush (stdin);"


Add a return statement.

What is the purpose of "div++;"?? You never initialize div... or x or num for that matter.

edit: beaten.

thanks salem, but now im geting 325. i ned to write a C program that accepts an int value and returns it s factroal if thats any help

one other small problem im having, i also need to make a program that subtracts one time from another, it is supposed to display in 24 h format, thing is i cant seem to get 00:00 hours to appear by subtracting two times that are the same ie 10:00 - 10:00 I have managed to get a display of 22:00 hoursso what am i doing wrong?
here is the code

Code:

#include <stdio.h>
#include <conio.h>

void main (void)
{
   int hours,hours2=0;
   int mins, mins2=0;
   clrscr();

   printf("Enter the time you reqire (hours) 24-h format: ");
   scanf("%d", &hours);
   fflush(stdin);
   printf("\n");
   printf("now enter the minutes: ");
   scanf("%d", &mins);
   fflush(stdin);

   if (hours >23)
      hours=0;
   if (mins >=60)
   {
      mins=mins-60;
      hours++;
   }
   printf("the time entered is %2d:%.2d\n", hours, mins);
   printf("\n");
   printf("Enter the time you wish to be subtracted (hours): ");
   scanf("%d", &hours2);
   fflush(stdin);
   printf("\n");
   printf("now enter the minutes: ");
   scanf("%d", &mins2);
   fflush(stdin);

   if ((hours2<hours) && (mins2<mins))
     {
      hours=hours2-hours;
      mins=mins2-mins;
     }
  else
    {
     hours=hours-hours2;
     mins=mins2-mins;
     hours--;
    }

   if (hours<0)
      hours=hours+23;




   printf("the time is now %.2d:%.2d", hours, mins);

}