islands.adb:39:31: medium: overflow check might fail[#3]
islands.ads:34:19: medium: contract cases might not be complete[#0]
islands.ads:34:38: medium: precondition might fail, cannot prove I < Integer'last (e.g. when I = Integer'Last-1)[#2]
islands.ads:34:105: medium: contract case might fail[#1]
