public override void CreateSamples(System.IO.StreamReader reader)
{
ReverseShuffleMergeSample sample = new ReverseShuffleMergeSample()
{
s = reader.ReadLine()
};
Samples.Add(sample);
}
public TAnswer BF(TSample Sample)
{
ReverseShuffleMergeSample sample = Sample as ReverseShuffleMergeSample;
String s = sample.s;
char[] result = new Char[s.Length / 2];
Int32 aPos = 'a';
Int32 zPos = 'z';
Int32[] cnt = new Int32[zPos - aPos + 1];
Int32 UniqueLetters = 0;
for (int i = 0; i < s.Length; i++)
{
cnt[s[i] - aPos]++;
}
Int32[] ap = new Int32[cnt.Length];
for (int i = 0; i < cnt.Length; i++)
{
ap[i] = cnt[i] / 2;
if (cnt[i] != 0)
{
UniqueLetters++;
}
}
Int32 ZeroesCount = 0;
Int32 ptr = 0;
for (int i = 0; i < s.Length; i++)
{
ap[s[i] - aPos]--;
if (ap[s[i] - aPos] == 0)
{
ZeroesCount++;
}
if (UniqueLetters == ZeroesCount)
{
ptr = i;
break;
}
}
Char min = 'z';
Int32 MinPtr = ptr;
for (int i = ptr; i < s.Length; i++)
{
if (min >= s[i])
{
min = s[i];
MinPtr = i;
}
}
result[0] = min;
Int32[] ReverseCnt = new Int32[cnt.Length];
Int32[] ShuffleCnt = new Int32[cnt.Length];
ReverseCnt[min - aPos]++;
for (int i = MinPtr + 1; i < s.Length; i++)
{
ShuffleCnt[s[i] - aPos]++;
}
Int32 pos = 1;
Int32 iptr = MinPtr - 1;
while (iptr >= 0 && pos != result.Length)
{
if (ReverseCnt[s[iptr] - aPos] == cnt[s[iptr] - aPos] / 2)
{
ShuffleCnt[s[iptr] - aPos]++;
iptr--;
continue;
}
if (ShuffleCnt[s[iptr] - aPos] == cnt[s[iptr] - aPos] / 2)
{
result[pos] = s[iptr];
ReverseCnt[s[iptr] - aPos]++;
iptr--;
pos++;
continue;
}
Int32[] tempCnt = new Int32[ShuffleCnt.Length];
Array.Copy(ShuffleCnt, tempCnt, ShuffleCnt.Length);
Int32 NewMinPtr = iptr;
for (int j = iptr; j >= 0; j--)
{
if (ReverseCnt[s[j] - aPos] < cnt[s[j] - aPos] / 2 && s[NewMinPtr] > s[j])
{
NewMinPtr = j;
}
if (tempCnt[s[j] - aPos] == cnt[s[j] - aPos] / 2)
{
break;
}
tempCnt[s[j] - aPos]++;
}
for (int j = iptr; j > NewMinPtr; j--)
{
ShuffleCnt[s[j] - aPos]++;
}
ReverseCnt[s[NewMinPtr] - aPos]++;
result[pos] = s[NewMinPtr];
pos++;
iptr = NewMinPtr - 1;
}
return(new ReverseShuffleMergeAnswer()
{
result = new string(result)
});
}