#include <stdio.h>
#include <math.h>
struct Triangle{
	int a;
	int b;
	int c;
};
 
double Triangle_area(struct Triangle now){
	double t=(now.a+now.b+now.c)/2.0;
	return sqrt(t*(t-now.a)*(t-now.b)*(t-now.c));
}
 
int main(void) {
	struct Triangle now={5,5,5};
 
	printf("三角形の3辺を入力してください\n");
	scanf("%d",&now.a);
	scanf("%d",&now.b);
	scanf("%d",&now.c);
 
	double s;
	s=Triangle_area(now);
	printf("a: %d\n",now.a);
	printf("b: %d\n",now.b);
	printf("c: %d\n",now.c);
	printf("三角形の面積：%lf",s);
	return 0;
}
 

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NQo1CjU=

5
5
5