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

void cartesian_to_polar(float x, float y, float *r, float *theta) {
	*r = sqrtf(x*x + y*y);
	*theta = y/x;
}

int main() {
	int rc;
	float x, y, r, theta;

	printf("x: ");
	rc = scanf("%f", &x);
	// check that scanf was successful by checking if it returned 1 (1 successfully scanned item)
	if (rc != 1) {
		printf("Please enter a real number\n");
		return 1;
	}

	printf("y: ");
	rc = scanf("%f", &y);
	if (rc != 1) {
		printf("Please enter a real number\n");
		return 1;
	}

	cartesian_to_polar(x, y, &r, &theta);
	printf("r=%f theta=%f\n", r, theta);

	return 0;
}