foo.c: In function 'main':
foo.c:5:9: error: expected ',' or ';' before 'int'
    5 |         int num=0;
      |         ^~~
foo.c:6:21: error: 'num' undeclared (first use in this function)
    6 |         scanf("%d",&num);
      |                     ^~~
foo.c:6:21: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:26: error: expected ';' before ':' token
    7 |         for(int i=2;i<num:i++){
      |                          ^
      |                          ;

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