public static void Main(string[] args)
int[] sequence = Console.ReadLine().Split().Select(int.Parse).ToArray();
int middleStartIndex = CalculateStartingIndex(sequence);
int middleEndIndex = CalculateEndingIndex(sequence);
PrintFoldSum(middleStartIndex, middleEndIndex, sequence, middleStartIndex - 1, Console.Out);
static int CalculateStartingIndex(int[] sequence)
int half = sequence.Length / 2;
static int CalculateEndingIndex(int[] sequence)
int half = sequence.Length / 2;
int end = half + CalculateStartingIndex(sequence);
static int TryMoveSummingIndexToEnd(int summingIndex, int[] sequence)
summingIndex = sequence.Length - 1;
static void PrintFoldSum(int middleStartIndex,
for (int i = middleStartIndex; i < middleEndIndex; i++)
int sum = sequence[i] + sequence[summingIndex];
summingIndex = TryMoveSummingIndexToEnd(summingIndex - 1, sequence);