Assignment 11: Dynamically (re)allocate scores array

Assignment-11/assignment11.c

@@ -1,44 +1,61 @@
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 
+#define INITIAL_CAPACITY 3
+
 int main(void)
 {
-  char answer[] = "Y";
+  char answer[] = "y";
 
-  float scores[10];
+  //allocate store for 3 scores
+  double *scores = malloc(INITIAL_CAPACITY * sizeof(double));
+  if(!scores)
+  {
+    fprintf(stderr, "Failed to allocate scores array.\n");
+    return 1;
+  }
+
+  int capacity = INITIAL_CAPACITY;
 
   //initialize a variable to increase and iterate through our array to store scores
-  int i = 0;
+  int numScores;
 
-  while (strcmp(answer, "Y") == 0)
+  for(numScores = 0; strcmp(answer, "y") == 0; ++numScores)
   {
+    //dynamically
+    if(numScores == capacity)
+    {
+      capacity *= 2;
+      scores = realloc(scores, capacity * sizeof(double));
+      if(!scores)
+      {
+        fprintf(stderr, "Failed to reallocate scores array.\n");
+        return 1;
+      }
+    }
 
     //store input in our array
     printf("Enter a test score: ");
-    scanf("%f", &scores[i]);
-
-    //increase our counter
-    i++;
+    scanf("%lf", &scores[numScores]);
 
     //ask the user if they would like to continue
-    printf("Would you like to continue? Y/N ");
+    printf("Would you like to continue? y/n ");
     scanf("%s", &answer);
   }
 
-  int loop;
-  int sum = 0;
+  double sum = 0;
 
   //start a loop that will start at 0, and then it'll iterate through our scores array until it reaches the end
   //each element in the array will be added to the sum so that we can find the average
-  for(loop = 0; loop < i; loop++)
+  for(int loop = 0; loop < numScores; loop++)
   {
-    sum = sum + scores[loop];
+    sum += scores[loop];
   }
 
-  //do the maths
-  float average;
+  printf("%.2f is the average.\n", sum / numScores);
 
-  average = (float)sum/loop;
+  free(scores);
 
-  printf("%.2f is the average.\n", average);
+  return 0;
 }