两个值求最大最小:
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						int a=12; int b=13; int max=Math.Max(a,b);//Math.Max()不能比较datetime int min=a<b?a:b;  | 
					
三个值求最大最小:
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						int a=12; int b=13; int c=14;  int max=a>b?(a>c?a:c):(b>c?b:c);  int min=a<b?(a<c?a:c):(b<c?b:c);  | 
					
多个值求最大最小:
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						int a = 12; int b = 13; int c = 14; int d = 15;  int max = new List<int> { a, b, c, d }.Max();  int min = new List<int> { a, b, c, d }.Min();  | 
					
