#include "stdio.h"
#include "stdlib.h"

float batataMedia(float *v1, float *v2) {

	float media = (*v1+*v2) / 2;
	*v1 = 0.0;
	*v2 = 0.0;
	return media;
}

int main()  {

	float v1, v2;
	scanf("%f %f", &v1, &v2);

	float media;
	media = batataMedia(&v1, &v2);
	printf("Batata media = %f\n", media);
	printf("v1 %f    v2 = %f\n", v1, v2);

	int n;
	scanf("%d", &n);
	float *f = (float*) calloc(n, sizeof(float));
	for (int i = 0; i < n; i++)
	{
		f[i] = rand() % 100;
	}

	for (int i = 0; i < 10; i++)
	{
		printf("f[%d] = %f\n", i, f[i]);
	}

	float tmp;
	tmp = f[0];
	f[0] = f[n-1];
	f[n-1] = tmp;
	printf("f[0] = %f\n", f[0]);
	printf("f[%d] = %f\n", n-1, f[n-1]);

	free(f);

	return 0;
}