C语言学习10

判断三角形的类型
根据输入的三角形的三条边判断三角形的类型，并输出它的面积。
 1 #include <stdio.h>
 2 #include <math.h>
 3 
 4 void judge_1(double x, double y, double z);
 5 
 6 void main()
 7 {
 8     double a, b, c;
 9     printf("输入三边 a b c: ");
10     scanf("%lf %lf %lf", &a, &b, &c);
11     judge_1(a, b, c);
12     printf("
");
13 }
14 
15 void judge_1(double x, double y, double z)
16 {
17     double m, s, area;
18     if(x>y)
19     {
20         m = y;
21         y = x;
22         x = m;
23     }
24     if(x>z)
25     {
26         m = z;
27         z = x;
28         x = m;
29     }
30     if(y>z)
31     {
32         m = z;
33         z = y;
34         y = m;
35     }
36 
37     if(x+y>z && z-y<x)
38     {
39         s = (x+y+z)/2.0;
40         area = sqrt(s*(s-x)*(s-y)*(s-z));
41         if(x == y && x== z)
42         {
43             printf("等边三角形-面积为:%lf
", area);
44         }
45         else if(x == y || y == z || x==z)
46         {
47             printf("等腰三角形-面积为:%lf
", area);
48         }
49         else if(x*x + y*y == z*z)
50         {
51             printf("直角三角形-面积为:%lf
", area);
52         }
53         else
54         {
55             printf("普通三角形-面积为:%lf
", area);
56         }
57     }
58     else
59     {
60         printf("不能构成三角形
");
61     }
62 }