double result = 0;

Console.Write("請(qǐng)選擇一種運(yùn)算：1、加法 2、減法 3、乘法 4、除 法"+"\n");

Console.Write("請(qǐng)選擇算法：");

double a = Convert.ToInt32(Console.ReadLine ());

Console.WriteLine("請(qǐng)輸入第一個(gè)數(shù)字：");

double b = Convert.ToInt32(Console.ReadLine());

Console.WriteLine("請(qǐng)輸入第二個(gè)數(shù)字：");

double c = Convert.ToInt32(Console .ReadLine ());

if(a==1)

{

result = b + c;

}

if (a==2)

{

if(c>b)

{

double temp = 0;

temp = c;

c = b;

b = temp;

}

result = b- c;

}

if(a==3)

{

result = b * c;

}

if(a==4)

{

if(c>b)

{

double t = 0;

t = c;

c = b;

b = t;

}

result = b / c;

}

Console.WriteLine();

Console.WriteLine("*********運(yùn)算結(jié)果是：{0}",result);

Console.ReadKey();