foo.c: In function 'main':
foo.c:29:5: warning: 'main' is normally a non-static function [-Wmain]
   29 | int main()
      |     ^~~~
foo.c:55:1: error: expected declaration or statement at end of input
   55 | }
      | ^
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d %d %d",&s1,&s2,&s3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
At top level:
foo.c:29:5: warning: 'main' defined but not used [-Wunused-function]
   29 | int main()
      |     ^~~~

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