/in/foo.c: In function 'main':
/in/foo.c:4:2: warning: implicit declaration of function 'gets' [-Wimplicit-function-declaration]
  gets(s);
  ^~~~
/in/foo.c:6:2: warning: implicit declaration of function 'scanf' [-Wimplicit-function-declaration]
  scanf("%d",&k);  
  ^~~~~
/in/foo.c:6:2: warning: incompatible implicit declaration of built-in function 'scanf'
/in/foo.c:6:2: note: include '<stdio.h>' or provide a declaration of 'scanf'
/in/foo.c:15:2: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
  printf("%s",s[10000]);
  ^~~~~~
/in/foo.c:15:2: warning: incompatible implicit declaration of built-in function 'printf'
/in/foo.c:15:2: note: include '<stdio.h>' or provide a declaration of 'printf'
/in/foo.c:15:11: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
  printf("%s",s[10000]);
           ^
/tmp/ccVrK8ZR.o: In function `main':
foo.c:(.text.startup+0xf): warning: the `gets' function is dangerous and should not be used.