private uint InsertString(ref uint hash) {
hash = this.HashValue(hash, this.window[this.bufPos + 2]);
uint num = this.lookup[hash & 0x7ff];
this.lookup[hash & 0x7ff] = (ushort)this.bufPos;
this.prev[this.bufPos & 0x1fff] = (ushort)num;
return num;
}