Program #37 (U4): malloc — Dynamic Array and Mean
Task: Read N, allocate an int array with malloc, input elements, compute the average, print it, and free the memory.
#include <stdio.h>
#include <stdlib.h>
int main(void){
int N, *a;
long long sum=0;
printf("Enter N (>0): ");
if(scanf("%d", &N)!=1 || N<=0){ printf("Invalid N.\n"); return 0; }
a = (int*)malloc(N * sizeof(int));
if(!a){ printf("Allocation failed.\n"); return 0; }
printf("Enter %d integers: ", N);
for(int i=0;i<N;++i){ scanf("%d", &a[i]); sum += a[i]; }
printf("Mean = %.2f\n", (N? sum/(double)N : 0.0));
free(a);return 0;
}