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程序名: 1240-三角形面积
作者: 李品毅
日期: 2024-05-26 11:22
说明: 无

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include

include

using namespace std;

int main() {

double a[3][2];
for (int i = 0; i < 3; i++)
	for (int j = 0; j < 2; j++)
		cin >> a[i][j];
double b, c, d, l, s;
b = sqrt(pow((a[0][0] - a[1][0]), 2) + pow((a[0][1] - a[1][1]), 2));
c = sqrt(pow((a[0][0] - a[2][0]), 2) + pow((a[0][1] - a[2][1]), 2));
d = sqrt(pow((a[1][0] - a[2][0]), 2) + pow((a[1][1] - a[2][1]), 2));
l = (b + c + d) / 2;
s = sqrt((l - b) * (l - c) * (l - d) * l);
printf("%.2lf", s);
return 0;

}