foo.c: In function 'main':
foo.c:27:4: warning: this 'else' clause does not guard... [-Wmisleading-indentation]
    else
    ^~~~
foo.c:30:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'else'
     return 0;
     ^~~~~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d%d",&a,&b,&c);
  ^~~~~~~~~~~~~~~~~~~~~~~~

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