Added input operation handler operation check

src/operationHandler.c

@@ -0,0 +1,10 @@
+#include "operationHandler.h"
+#include <stdbool.h>
+
+bool checkOperationInput(int input) {
+    switch (input) {
+        case 4: case 3: case 2: case 1:
+            return true;
+    }
+    return false;
+}

src/operationHandler.h

@@ -0,0 +1,7 @@
+#ifndef THEADMIRALS_OPERATIONHANDLER_H
+#define THEADMIRALS_OPERATIONHANDLER_H
+#include <stdbool.h>
+
+bool checkOperationInput(int);
+
+#endif //THEADMIRALS_OPERATIONHANDLER_H