foo.c: In function 'main':
foo.c:11:3: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
   else
   ^~~~
foo.c:13:4: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
    i++;
    ^
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d",&a);
  ^~~~~~~~~~~~~~

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