/in/foo.cc: In function 'int main()':
/in/foo.cc:6:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(a);//scanf("%s\n",a);
  ^~~~
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:6:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(a);//scanf("%s\n",a);
        ^
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:7:2: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(b); 
  ^~~~
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:7:8: warning: 'char* gets(char*)' is deprecated [-Wdeprecated-declarations]
  gets(b); 
        ^
In file included from /in/foo.cc:1:0:
/usr/include/stdio.h:640:14: note: declared here
 extern char *gets (char *__s) __wur __attribute_deprecated__;
              ^~~~
/in/foo.cc:44:25: warning: 'x' may be used uninitialized in this function [-Wmaybe-uninitialized]
  printf("%d %d\n",sum,x);
                         ^
/tmp/ccUcOSSi.o: In function `main':
foo.cc:(.text.startup+0x4b): warning: the `gets' function is dangerous and should not be used.