private static List <BlockedIPRange> GetBlockedIPRanges()
{
StreamReader file = new StreamReader("input20.txt");
List <BlockedIPRange> blockedIPRanges = new List <BlockedIPRange>();
string line;
while ((line = file.ReadLine()) != null)
{
string[] startAndEnd = line.Split('-');
uint rangeStart = Convert.ToUInt32(startAndEnd[0]);
uint rangeEnd = Convert.ToUInt32(startAndEnd[1]);
BlockedIPRange nextBlockedIPRange = new BlockedIPRange(rangeStart, rangeEnd);
blockedIPRanges.Add(nextBlockedIPRange);
}
return(blockedIPRanges);
}
private static uint FindLowestAllowedIP(List <BlockedIPRange> blockedIPRanges)
{
uint highestEnd = blockedIPRanges[0].GetEnd();
for (int i = 0; i < blockedIPRanges.Count - 1; i++)
{
BlockedIPRange range = blockedIPRanges[i];
BlockedIPRange nextRange = blockedIPRanges[i + 1];
if (range.GetEnd() > highestEnd)
{
highestEnd = range.GetEnd();
}
if (nextRange.GetStart() > highestEnd + 1)
{
return(highestEnd + 1);
}
}
throw new Exception("All IPs are blocked. Sorry");
}
private static uint FindNumAllowedIPs(List <BlockedIPRange> blockedIPRanges)
{
uint numAllowedIPs = 0;
uint highestEnd = blockedIPRanges[0].GetEnd();
for (int i = 0; i < blockedIPRanges.Count - 1; i++)
{
BlockedIPRange range = blockedIPRanges[i];
BlockedIPRange nextRange = blockedIPRanges[i + 1];
if (range.GetEnd() > highestEnd)
{
highestEnd = range.GetEnd();
}
if (nextRange.GetStart() - 1 > highestEnd)
{
numAllowedIPs += nextRange.GetStart() - highestEnd - 1;
highestEnd = nextRange.GetEnd();
}
}
return(numAllowedIPs);
}
