foo.c: In function 'main':
foo.c:6:17: warning: format '%i' expects argument of type 'int *', but argument 2 has type 'double *' [-Wformat=]
    6 |         scanf("%if",&r);
      |                ~^   ~~
      |                 |   |
      |                 |   double *
      |                 int *
      |                %le

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