foo.c: In function 'main':
foo.c:7:2: warning: implicit declaration of function 'gets' [-Wimplicit-function-declaration]
  gets(s);
  ^~~~
foo.c:10:2: warning: implicit declaration of function 'printf' [-Wimplicit-function-declaration]
  printf("%d\n",m);
  ^~~~~~
foo.c:10:2: warning: incompatible implicit declaration of built-in function 'printf'
foo.c:10:2: note: include '<stdio.h>' or provide a declaration of 'printf'
/tmp/ccCvUDqN.o: In function `main':
foo.c:(.text.startup+0x2b): warning: the `gets' function is dangerous and should not be used.

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