Added 2 new questions (#2298)

Added 2 new questions but without a correct answer.

c-(programming-language)/c-quiz.md

@@ -451,3 +451,56 @@ printf("%d", f1(5));
 - [x] `char string = "Hello World";`
 - [ ] `char string[20] = {'H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd'};`
 - [ ] `char string[] = "Hello World";`
+
+#### Q35. Which choice is an include guard for the header file mylib.h?
+
+- [ ] 
+```c
+#ifdef MYLIB_H
+#undef MYLIB_H
+
+// mylib.h content
+
+#endif /* MYLIB_H */
+```
+- [ ] 
+```c
+#ifndef MYLIB_H
+#define MYLIB_H
+
+// mylib.h content
+
+#endif /* MYLIB_H */
+```
+- [ ] 
+```c
+#define MYLIB_H
+#include "mylib.h"
+
+#undef MYLIB_H
+```
+- [ ] 
+```c
+#ifdef MYLIB_H
+#define MYLIB_H
+
+// mylib.h content
+
+#endif /* MYLIB_H */
+```
+#### Q36. How many times does the code inside the while loop get executed in this program?
+```c
+main(){
+ int x=1;
+ while(x++<100){
+    x*=x;
+    if(x<10) continue;
+    if(x>50) break
+ }
+}
+```
+
+- [ ] 100
+- [ ] 3
+- [ ] 5
+- [ ] 50