foo.c:28:5: error: redefinition of 'px'
   28 | int px(int x1,int x2,int x3)
      |     ^~
foo.c:2:5: note: previous definition of 'px' was here
    2 | int px(int x1,int x2,int x3)
      |     ^~
foo.c:46:5: error: redefinition of 'main'
   46 | int main()
      |     ^~~~
foo.c:20:5: note: previous definition of 'main' was here
   20 | int main()
      |     ^~~~
foo.c: In function 'main':
foo.c:22:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   22 |  int x1;scanf("%d",&x1);
      |         ^~~~~~~~~~~~~~~
foo.c:23:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   23 |  int x2;scanf("%d",&x2);
      |         ^~~~~~~~~~~~~~~
foo.c:24:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   24 |  int x3;scanf("%d",&x3);
      |         ^~~~~~~~~~~~~~~
foo.c: In function 'px':
foo.c:44:1: warning: control reaches end of non-void function [-Wreturn-type]
   44 | }
      | ^
foo.c: In function 'main':
foo.c:48:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   48 |  int x1;scanf("%d",&x1);
      |         ^~~~~~~~~~~~~~~
foo.c:49:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   49 |  int x2;scanf("%d",&x2);
      |         ^~~~~~~~~~~~~~~
foo.c:50:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   50 |  int x3;scanf("%d",&x3);
      |         ^~~~~~~~~~~~~~~

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