foo.c: In function 'main':
foo.c:14:28: warning: format '%f' expects argument of type 'double', but argument 2 has type 'int' [-Wformat=]
   14 |                 printf("y=%f",a*k-m);
      |                           ~^  ~~~~~
      |                            |     |
      |                            |     int
      |                            double
      |                           %d
foo.c:5:15: warning: variable 'y' set but not used [-Wunused-but-set-variable]
    5 |     int a,m,k,y;
      |               ^

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