Added isPrime.c

Checks if a number (n) is a prime, also lists all it's factors

isPrime.c

@@ -0,0 +1,31 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char* argv[])
+{
+    if (argc != 2)
+    {
+        printf("Usage = ./isPrime <n>");
+        return -1;
+    }
+    
+    int n = atoi(argv[1]);
+    int results = 0;
+    
+    for (int i = 1; i < n + 1; i++)
+    {
+        if (n % i == 0)
+        {
+            printf("%i is divisible by %i\n", n, i);
+            results++;
+        }
+    }
+    if (results == 2)
+    {
+        printf("%i is a prime.\n", n);
+    }
+    else
+    {
+        printf("%i is not a prime, as it's divisible by %i numbers other than 1 and %i\n", n, results - 2, n);
+    }
+}