AOJ 10025 - Triangle, math.hをincludeするとき
math.hをincludeするときは-lmオプションをつける
#include <math.h> main(){ double a, b, C; scanf("%lf %lf %lf", &a, &b, &C); double rad = C*M_PI/180, S = a*b*sin(rad)/2, h = b*sin(rad), ar = a+b+sqrt(a*a+b*b-2*a*b*cos(rad)); printf("%lf\n%lf\n%lf\n", S, ar, h); return 0; }