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

int main()
{
    int x;
    scanf("%d", &x);
    if(x <= 0){
        printf("y: %d", (2*x*x - 5));
    }
    else if((x > 0) && (x <= 4)){
        printf("y: %d", (x*x*x + 2*x*x + 1));
    }
    else if((x > 4) && (x < 10)){
        printf("y: %d", (x*x + x));
    }
    else if(x >= 10){
        printf("y: %f", (sqrt(x)));
    }

    return 0;
}