foo.c: In function 'main':
foo.c:8:9: error: variable-sized object may not be initialized
    8 |         int a[L+1]={0}
      |         ^~~
foo.c:9:9: error: expected ',' or ';' before 'for'
    9 |         for(int i=0;i<=M;i++)
      |         ^~~
foo.c:9:21: error: 'i' undeclared (first use in this function)
    9 |         for(int i=0;i<=M;i++)
      |                     ^
foo.c:9:21: note: each undeclared identifier is reported only once for each function it appears in
foo.c:9:29: error: expected ';' before ')' token
    9 |         for(int i=0;i<=M;i++)
      |                             ^
      |                             ;
foo.c:9:29: error: expected statement before ')' token
foo.c:16:31: error: expected ';' before '}' token
   16 |                         a[j]=1
      |                               ^
      |                               ;
   17 |                 }
      |                 ~              
foo.c:8:13: warning: variable 'a' set but not used [-Wunused-but-set-variable]
    8 |         int a[L+1]={0}
      |             ^

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