#define how to use with is code ?

krish_kumar

int main() { printf("Enter 0 or 1 :"); scanf("%d",&i_choice); if ( i_choice ==0 ) for( ;i_count_1 < i_number;) {------- ------ } if (choice == 1) for( ;i <= i_number;) {------- ------ } Here I raed a user input ( 0 or 1) So as per i/p I've to change the condition in my for loop. if choice ==1 the condition must be (i <= i_number) if choice == 0 the condition must be (i_count_1 < i_number) I don't know how to use #define with this program. anybody can help me.... Krish

Maxwell Chen

You don't need #define in your code sample, but you need a switch(i_choice).

Maxwell Chen

krish_kumar

here I wanna reduce the code size.... swith(i_choice) { case 0 : for (.. ; condition 1 ; ..) { } break; case 1 : for (.. ; condition 2 ; ..) { } break; } So the code will come twise ; except the conditions in for loop all other statements are same for case 1 and 0. That's why I tried for a #define Macro. ???? with regards Krish

Maxwell Chen

krish_kumar wrote:

case 0 : for (.. ; condition 1 ; ..)

Then could you show the complete code (I mean those ... portions)? I will figure out a solution for you.

Maxwell Chen

David Crow

krish_kumar wrote:

That's why I tried for a #define Macro. ????

Which would be totally wrong. The #define directive is handled by the preprocessor before the compile phase. You don't know the value of i_choice until the code is running. See the problem?

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

krish_kumar

Okkk... I realize I can't use a #define here.... But my code is repeating twice ...I wanna avoid that.... Except condition the other statements are same for both... Here is my code printf("\n U wanna find prime nos up to N(press 1) or N prime nos (press 0 "); scanf("%d",&i_choice); switch(i_choice) { case 0 : for (i = 1, i_count = 0; i_count_1 < i_number; i++ ) { for (j = 1,i_count = 0; j <= i ; j++) { if ((i % j) == 0) ++i_count; } if (i_count <= 2) { printf("\t %d \n",i); i_count_1++; } } break; case 1 : for (i = 1, i_count = 0 ; i <= i_number; i++ ) { for (j = 1, i_count = 0; j <= i ; j++) { if( (i % j)==0 ) ++i_count; } if (i_count <= 2) { printf("\t %d \n",i); i_count_1++; } } } }

Maxwell Chen

I would suggest you to re-design your code architecture. See the sample code below.

#include <iostream>

int GetNextPrime(int iStartNum)
{
int i, j;
int i_count;
for(i = iStartNum; ; i++) {
for(j = 1, i_count = 0; j <= i ; j++) {
if( (i % j) == 0 )
++i_count;
}
if(i_count <= 2) {
return i;
}
}
return 0;
}

void main()
{
int i_choice;
int i_count;
int i_count_1 = 0;
int i_number = 10;
int i, j;
int iValNow;
int count;

printf("Find prime nos up to %d (press 1), or %d prime nos (press 0) ", i\_number, i\_number);
scanf("%d", &i\_choice);


// ---------------------------------------------------------
printf("\\n My version: \\n");
switch(i\_choice)
{
case 0 :	// N count.
	for(i = 0, iValNow = i, count = 0; count < i\_number; i++, count++) {
		iValNow = GetNextPrime(iValNow +1);
		printf("\\t %d \\n", iValNow);			
	}
	break;
case 1 :	// up to N.
	for(iValNow = 0; ; ) {
		iValNow = GetNextPrime(iValNow +1);
		if(iValNow > i\_number) {
			break;
		}
		printf("\\t %d \\n", iValNow);
	}
	break;
}

// ---------------------------------------------------------
printf("\\n Your version: \\n");

switch(i\_choice)
{
case 0 :	// N count.
	for(i = 1, i\_count = 0; i\_count\_1 < i\_number; i++ ) {
		for(j = 1,i\_count = 0; j <= i ; j++) {
			if( (i % j) == 0 )
				++i\_count;
		}
		if(i\_count <= 2) {
			printf("\\t %d \\n",i);
			i\_count\_1++;
		}
	}
	break;

case 1 :	// up to N.
	for(i = 1, i\_count = 0 ; i <= i\_number; i++ ) {
		for(j = 1, i\_count = 0; j <= i ; j++) {
			if( (i % j) == 0 )
				++i\_count;
		}
		if(i\_count <= 2) {
			printf("\\t %d \\n",i);
			i\_count\_1++;
		}
	}
}

}

Maxwell Chen

David Crow

krish_kumar wrote:

But my code is repeating twice ...I wanna avoid that....

No problem. Just put the common code in a function.

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons