#include <stdio.h>
#include <math.h>
int main(void) {
    double alpha;
    double x, y, z;
    printf("Enter x value\n");
    scanf("%lf", &x);

    printf("Enter y value\n");
    scanf("%lf", &y);

    printf("Enter z value\n");
    scanf("%lf", &z);

    printf("x = %lf\n", x);
    printf("y = %lf\n", y);
    printf("z = %lf\n", z);
    if (y <= 0)
    {
        printf("error\n");
        return 0;
    }
    if (y > 0)
    {
        alpha = log(pow(y, -sqrt(abs(x)))) * (x - y / 2) + pow(sin(atan(z)), 2);
        printf("alpha = %lf", alpha);
    }
    return 0;
}