Daniel Lawson Pennies Program

#include <stdio.h>
#include <cs50.h>
#include <math.h>

int main(void){
    int days = 0;
    int pennies = 0;
    long double val = 0;
    while(!(days >= 28 && days <= 31)){//ask for days until they ask for a value from [28,31]
        printf("Days in month: ");
        days = get_int();

    }
    while(pennies <= 0){//ask for pennies until they give a positive nonzero number
        printf("Pennies on the first day: ");
        pennies = get_int();

    }
    for(int i = 0; i<days;i++)val += pennies*pow(2,i);//calculate the total amount
    val /= 100;//convert to dollars
    printf("$%.2Lf\n",val);//print the value, only display until the hundreth place
}