foo.c: In function 'main':
foo.c:7:9: error: expected ',' or ';' before 'int'
    7 |         int num[10],maxheight;
      |         ^~~
foo.c:9:29: error: 'num' undeclared (first use in this function)
    9 |                 scanf("%d",&num[i]);
      |                             ^~~
foo.c:9:29: note: each undeclared identifier is reported only once for each function it appears in
foo.c:11:21: error: 'maxheight' undeclared (first use in this function)
   11 |         scanf("%d",&maxheight);
      |                     ^~~~~~~~~
foo.c:14:28: error: expected ';' before '}' token
   14 |                         n++
      |                            ^
      |                            ;
   15 |                         }
      |                         ~   

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