foo.c: In function 'main':
foo.c:10:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:14:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:18:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:22:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:26:7: error: expected ';' before ':' token
    i++:
       ^
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&l,&r);
  ^~~~~~~~~~~~~~~~~~~~

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