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

double fahrToCels(double fahr);
void inputFahrs(double * data, int numFahrs);
void outputFahrs(double * data, int numFahrs);
void outputAverage(const double * data, int numFahrs);
void outputHighLows(const double * data, int numFahrs);
void outputStdDev(const double * data, int numFahrs);

int main() {
   int numFahrs;
   printf("Please enter the amount, between 1-20, of Fahrenheit temperatures > ");
   scanf("%i", &numFahrs);
   while (numFahrs > 20 || numFahrs < 1) {
       printf("That value is out of range\n");
       printf("Please enter the amount, between 1-20, of Fahrenheit temperatures > ");
       scanf("%i", &numFahrs);
   }
   double *data;
   data = (double *) malloc(sizeof (double) * numFahrs);

   inputFahrs(data, numFahrs);
   outputFahrs(data, numFahrs);
   outputAverage(data, numFahrs);
   outputHighLows(data, numFahrs);
   outputStdDev(data, numFahrs);

   free(data);
   return 0;
}

void inputFahrs(double * data, int numFahrs) {
   int i;
   for (i = 0; i < numFahrs; i++) {
       printf("Value [%i] > ", i);
       scanf("%lf", &data[i]);
       while (data[i] > 200.0 || data[i] < -200.0) {
           printf("Out of Range");
           printf("Re-enter Value");
           scanf("%lf", &data[i]);
       }
   }
}

double fahrToCels(double fahr) {
   return (fahr - 32) * 5 / 9;
}

void outputFahrs(double * data, int numFahrs) {
   /*selection sort*/
   int i, j, temp;
   for (i = 0; i < numFahrs; i++) {
       for (j = i + 1; j < numFahrs; j++) {
           if (data[i] > data[j]) {
               temp = data[i];
               data[i] = data[j];
               data[j] = temp;
           }
       }

   }
   printf("                    Fahr       Cels\n");
   printf("                   ======     ======\n");
   for (i = 0; i < numFahrs; i++) {

       printf("              %10.1lf %10.1lf\n", data[i], fahrToCels(data[i]));
   }
	   printf("                   ======     ======\n");
}

void outputAverage(const double * data, int numFahrs) {
   double sumFahr = 0, sumCels = 0, Favg, Cavg;
   int i;
   for (i = 0; i < numFahrs; i++) {
       sumFahr = sumFahr + data[i];
       sumCels = sumCels + fahrToCels(data[i]);
   }
   Favg = sumFahr / numFahrs;
   Cavg = sumCels / numFahrs;
   printf("Average:      %10.1lf %10.1lf\n\n", Favg, Cavg);
}

void outputHighLows(const double * data, int numFahrs) {
   int i;
   double Fhigh = data[0], Flow = data[0];

   for (i = 0; i < numFahrs; i++) {
       if (data[i] > Fhigh) {
           Fhigh = data[i];
       }
       if (data[i] < Flow) {
           Flow = data[i];
       }
   }

   double Chigh = fahrToCels(data[0]), Clow = fahrToCels(data[0]);
   for (i = 0; i < numFahrs; i++) {
       if (fahrToCels(data[i]) > Chigh) {
           Chigh = fahrToCels(data[i]);
       }
       if (fahrToCels(data[i]) < Clow) {
           Clow = fahrToCels(data[i]);
       }
   }
   printf("High:         %10.1lf %10.1lf\n", Fhigh, Chigh);
   printf("Low:          %10.1lf %10.1lf\n\n", Flow, Clow);
}

void outputStdDev(const double * data, int numFahrs) {
   double sumFahr = 0, Fstdsum = 0, Favg, Fstdavg;
   int i;
   for (i = 0; i < numFahrs; i++) {
       sumFahr = sumFahr + data[i];
   }
   Favg = sumFahr / numFahrs;

   for (i = 0; i < numFahrs; i++) {
       Fstdsum += (Favg - data[i]) * (Favg - data[i]);
   }
   Fstdavg = sqrt(Fstdsum / (numFahrs - 1));
   printf("Standard Deviation: %3.1lf\n", Fstdavg);
}