#include<stdio.h>
struct structure
{
    float BMI;
};
int main()
{
    struct structure a;
    scanf("%f",&a.BMI);
    if
    {
        printf("Invalid input");
    }
    else if(a.BMI<18.5)
    {
        printf("Underweight");
    }
    else if((a.BMI>18.5)&&(a.BMI<24.9))
    {
        printf("Normal weight");
    }
    else
    {
        printf("Overweight");
    }
    return 0;
}