foo.c: In function 'main':
foo.c:6:3: error: expected '=', ',', ';', 'asm' or '__attribute__' before 'while'
   while (scanf("%d%d",&a,&b) != EOF)
   ^~~~~
foo.c:5:6: warning: unused variable 'a' [-Wunused-variable]
  int a,b
      ^

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