//面积公式s = (a+b+c) / 2 area = sqrt(s * (s - a) * (s - b) * (s - c));
//小作业 求三角形的面积
int check(double a);
int check2(double a, double b, double c);
#include
#include
int main(void)
{
double area = 0;
double s;
double a,b,c;
printf("请输入三角形的三边的长(a b c):");
scanf("%lf %lf %lf", &a, &b, &c);
if (check(a) == 1 && check(b) == 1 && check(c) ==1)
{
if (check2(a,b,c) == 0)
{
printf("您输入的不是三角形.请重新输入nr");
return 0;
}
else if (check2(a,b,c) == 1)
{
s = (a+b+c) / 2;
area = sqrt(s * (s - a) * (s - b) * (s - c));
printf("该三角形的面积是:%gnr",area);
}
}
else
printf("输入有误,请重新输入.nr");
return 0;
}
//判断输入的数据是否有效
int check(double a)
{
if (a > 0)
return 1;
else
return 0;
}
//判断三角形是否有效
int check2(double a, double b, double c)
{
if ( ((a+b)=a)
return 0;
else
return 1;
}
