foo.c: In function 'GTA':
foo.c:6:2: warning: statement with no effect [-Wunused-value]
    6 |  for(i;i<j;i++)
      |  ^~~
foo.c: In function 'main':
foo.c:19:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   19 |  scanf("%d",&a);
      |  ^~~~~~~~~~~~~~

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