foo.c: In function 'main':
foo.c:12:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:16:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:20:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:24:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:28:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&l,&r);
  ^~~~~~~~~~~~~~~~~~~~

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