我写了一个简短的脚本来计算斐波那契数列，只是为了好玩。使用Uint64，序列应在x=> 18,446,744,073,709,551,616时停止。
但是，当序列趋向无穷大时，我得到的东西就非常不同，有时值会减小。
这是我的算法：
static void Main(string[] args)
{
bool Error = false;
UInt64 X = 1;
UInt64 Y = 1;
UInt64 Z = 0;
DateTime Start = DateTime.Now;
while (!Error)
{
try
{
Z = X + Y;
Console.Out.WriteLine(Z.ToString("0,0"));
X = Y;
Y = Z;
}
catch
{
Error = true;
}
}
Console.Out.WriteLine("Max value reachd: " + Z.ToString());
TimeSpan Duration = DateTime.Now - Start;
Console.Out.WriteLine("This took" +
Duration.TotalSeconds.ToString() + " seconds");
Console.In.ReadLine();
}
有人可以解释这种行为吗？
这是输出示例：
4,808,835,623,615,708,056
5,982,022,270,976,898,581
10,790,857,894,592,606,637
16,772,880,165,569,505,218
9,116,993,986,452,560,239
7,443,130,078,312,513,841
16,560,124,064,765,074,080
5,556,510,069,368,036,305
3,669,890,060,423,558,769
9,226,400,129,791,595,074
12,896,290,190,215,153,843
3,675,946,246,297,197,301
16,572,236,436,512,351,144
1,801,438,609,099,996,829
18,373,675,045,612,347,973
1,728,369,581,002,793,186
1,655,300,552,905,589,543
3,383,670,133,908,382,729
5,038,970,686,813,972,272
8,422,640,820,722,355,001
13,461,611,507,536,327,273
请注意，当值应该抛出异常时，该值会翻转并继续计算。