feat(solutions): add prefix-suffix/c/function

challenges/prefix-suffix/solutions/c/function/solution.c

@@ -0,0 +1,18 @@
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "input.h"
+#include "string.h"
+
+int main() {
+  char* string = input();
+  char* string2 = input();
+  bool is_preffix = string_starts_with(string, string2);
+  bool is_suffix = string_ends_with(string, string2);
+  free(string);
+  free(string2);
+  printf("%s\n", is_preffix ? "true" : "false");
+  printf("%s\n", is_suffix ? "true" : "false");
+  return EXIT_SUCCESS;
+}