foo.c: In function 'main':
foo.c:7:13: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'char (*)[20]' [-Wformat=]
    7 |     scanf("%s",&a,20);
      |            ~^  ~~
      |             |  |
      |             |  char (*)[20]
      |             char *
foo.c:7:11: warning: too many arguments for format [-Wformat-extra-args]
    7 |     scanf("%s",&a,20);
      |           ^~~~

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