need help using do/while loop

juncas17 · 10-10-2009, 02:13 AM

i have code here in C programming that will convert decimal to binary, octal and hexa..
i already know how to use do/while loop but i'm difficulty on using the looping in my code that i made. for example

[1] Decimal to Binary
[2] Decimal to Octal
[3] Decimal to Hexadecimal
[4] Exit

Enter your choice: 1

Enter decimal number: 2009

Binary is: bla bla bla

Do you want to continue?(Y/N): Y

when i press Y i want that it will go back to first thing that you will choose again what conversion you want...can someone help me with my prob?

here is the code:

Code:

#include <stdio.h>

void main()
{
	void welcome();
	void code();
	int d;
	int i=0,n,j,b[100];
	
	printf("\t\t****************************************");
	printf("\n\t\t*\t\t\t\t       *");
	printf("\n\t\t*\t\t\t\t       *");
	printf("\n\t\t*          DECIMAL CONVERSION          *");
	printf("\n\t\t*\t\t\t\t       *");
	printf("\n\t\t*\t\t\t\t       *");
	printf("\n\t\t****************************************");
	code();
	scanf("%d", &d);
	
	switch(d)
	{
	case 1:	

	printf("\n\t\tEnter decimal number: ");
	scanf("%d", &n);

	while (n>0)
	{
		b[i]=n%2;
		n=n/2;
		i++;

	}

	printf("\n\t\tBinary is: ");
			j=i-1;

	for (i=j;j>=0;j--)
	{
		printf("%d", b[j]);

	}
	break;

	case 2:	
	printf("\n\t\tEnter decimal number: ");
	scanf("%d", &n);

	while (n>0)
	{
		b[i]=n%8;
		n=n/8;
		i++;
	}

	printf("\n\t\tOctal is:");
			j=i-1;

	for (i=j;j>=0;j--)
	{
		printf("%d", b[j]);
	}

	break;

	case 3:
	printf("\n\t\tEnter decimal number: ");
	scanf("%d", &n);

	while (n>0)
	{
		b[i]=n%16;
		n=n/16;
		i++;
	}

	printf("\n\t\tHexadecimal is:");
			j=i-1;

	for (i=j;j>=0;j--)
	{
		printf("%d", b[j]);
	
	if(b[j]<10)
	{
		printf("%d", b[j]);
	}
	else
	{
	switch(b[j])
	{
	case 10: 
		printf("A");
		break;
	case 11: 
		printf("B");
		break;
	case 12: 
		printf("C");
		break;
	case 13: 
		printf("D");
		break;
	case 14: 
		printf("E");
		break;
	case 15: 
		printf("F");
		break;
	}
	}
	}
	
}



}

void code ()  
{
	printf("\n\n\t\tChoose:\n");
	printf("\n\n\t\t[1] Decimal to Binary\n");
	printf("\t\t[2] Decimal to Octal\n");
	printf("\t\t[3] Decimal to Hexadecimal\n");
	printf("\t\t[4] Exit\n");

	printf("\n\n\t\tEnter your choice: ");
}

Adak · 10-10-2009, 02:22 AM

Sight unseen, the mystic forces tell me, you need to pull the newline char off the keyboard buffer with something like this:

Code:

char ch;
ch = getchar();

Put that ch = getchar(), right after your scanf(). It will remove the '\n' char from the keyboard buffer (which you get when you hit enter).

Numbers and strings are not affected this way, but char's with scanf(), always have this problem. If you still have problems, check that you have used two equal signs in your comparison with 'y' or 'Y', and not just one (which is an assignment).

Code:

do {
   //your other code in here

}while (ch == 'Y' || ch == 'y');

quzah · 10-10-2009, 02:25 AM

Code:

do
{
    showmenu();
    for( choice = getchoice(); !choiceinrange(); choice = getchoice() );
    handlechoice( choice );
}
while( choice != exitchoice );

There's the basic logic behind it.

Quzah.

10-10-2009, 02:22 AM	#2
Adak Registered User Join Date: Sep 2006 Posts: 2,512	Sight unseen, the mystic forces tell me, you need to pull the newline char off the keyboard buffer with something like this: Code: char ch; ch = getchar(); Put that ch = getchar(), right after your scanf(). It will remove the '\n' char from the keyboard buffer (which you get when you hit enter). Numbers and strings are not affected this way, but char's with scanf(), always have this problem. If you still have problems, check that you have used two equal signs in your comparison with 'y' or 'Y', and not just one (which is an assignment). Code: do { //your other code in here }while (ch == 'Y' \|\| ch == 'y'); Last edited by Adak; 10-10-2009 at 02:27 AM.
Adak is offline

10-10-2009, 02:25 AM	#3
quzah +++ OK NO CARRIER Join Date: Oct 2001 Posts: 10,262	Code: do { showmenu(); for( choice = getchoice(); !choiceinrange(); choice = getchoice() ); handlechoice( choice ); } while( choice != exitchoice ); There's the basic logic behind it. Quzah. __________________ Hundreds of thousands of dipshits can't be wrong. Are you up for the suck?
quzah is offline

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