Thread: if-statment not working

For some reason I can not get the if statements at the end to work. Atleast one of the if statements should work during each run of the program. Thanks in advance.

Code:

#include <stdio.h>
#include <math.h>

int main() {

	int x1,x2,x3,y1,y2,y3,a1,a2,a3,a4,a5,a6;
	double c12 = 0,c13 = 0,c23 = 0;

	printf("What are the first x and y coordinates?\n");
	scanf("%d %d", &x1, &y1);
	printf("What are the second x and y coordinates?\n");
	scanf("%d %d", &x2, &y2);
	printf("What are the third x and y coordinates?\n");
	scanf("%d %d", &x3, &y3);
	
	c12 = (pow(x2 - x1,2) + pow(y2 - y1,2));
	c12 = sqrt(c12);
	printf("%.2lf\n", c12);
	c13 = (pow(x3 - x1,2) + pow(y3 - y1,2));
	c13 = sqrt(c13);
	printf("%.2lf\n", c13);
	c23 = (pow(x3 - x2,2) + pow(y3 - y2,2));
	c23 = sqrt(c23);
	printf("%.2lf\n", c23);

	if (c12 + c13 == c23){
		a1 = (x2 + x3)/2; 
		a2 = (y2 + y3)/2;
		printf("(%d,%d) is the point in the middle", a1, a2);
		}
	if (c12 + c23 == c13){
		a3 = (x1 + x3)/2;
		a4 = (y1 + y3)/2;
		printf("(%d,%d) is the point in the middle", a3, a4);
		}
	if (c23 + c13 == c12){
		a5 = (x1 + x2)/2;
		a6 = (y1 + y2)/2;
		printf("(%d,%d) is the point in the middle", a5, a6);
		}

tried that after I posted. Still same result

The if- statements are still not working. This is what I have:

Code:

#include <stdio.h>
#include <math.h>

int main() {

	int x1,x2,x3,y1,y2,y3,a1,a2,a3,a4,a5,a6;
	double c12 = 0,c13 = 0,c23 = 0;

	printf("What are the first x and y coordinates?\n");
	scanf("%d %d", &x1, &y1);
	printf("What are the second x and y coordinates?\n");
	scanf("%d %d", &x2, &y2);
	printf("What are the third x and y coordinates?\n");
	scanf("%d %d", &x3, &y3);
	
	c12 = (pow(x2 - x1,2) + pow(y2 - y1,2));
	c12 = sqrt(c12);
	printf("%.2lf\n", c12);
	c13 = (pow(x3 - x1,2) + pow(y3 - y1,2));
	c13 = sqrt(c13);
	printf("%.2lf\n", c13);
	c23 = (pow(x3 - x2,2) + pow(y3 - y2,2));
	c23 = sqrt(c23);
	printf("%.2lf\n", c23);

	if ((c12 + c13) == c23){
		a1 = (x2 + x3)/2; 
		a2 = (y2 + y3)/2;
		printf("(%d,%d) is the point in the middle", a1, a2);
		}
	else if ((c12 + c23) == c13){
		a3 = (x1 + x3)/2;
		a4 = (y1 + y3)/2;
		printf("(%d,%d) is the point in the middle", a3, a4);
		}
	else if ((c23 + c13) == c12){
		a5 = (x1 + x2)/2;
		a6 = (y1 + y2)/2;
		printf("(%d,%d) is the point in the middle", a5, a6);
		}
		
		
	
	return 0;

}

I figured out where my problem is but I need help correcting it. For some reason my distance formula is not working out. It should work out that the two smallest distances should equal the bigger distance. Dosent that make sense?

Also, you shouldn't compare two floating point numbers with ==. Please see http://www.c-faq.com/fp/fpequal.html