2281.cpp

这是哈尔滨工业大学acmOJ的源代码

/*  This Code is Submitted by wywcgs for Problem 2281 on 2006-07-23 at 15:11:59 */ 
#include <cstdio>
#include <cmath>
#include <algorithm>
using namespace std;

const int N = 10240;

int l[N], alpha[N];

class Crane {
private:
	void update();
public:
	int b, e, pdg;
	double len, dg;
	Crane *left, *right;
	Crane(int, int);
	~Crane() { if(left != NULL) { delete left; delete right; } }
	void rotate(int, int);
	double xc() const { return len*cos(dg*M_PI/180); }
	double yc() const { return len*sin(dg*M_PI/180); }
};
void Crane::update() {
	double x = left->xc()+right->xc(), y = left->yc()+right->yc();
	len = sqrt(x*x+y*y); dg = atan2(y, x)*180/M_PI;
}
Crane::Crane(int cb, int ce) : b(cb), e(ce), pdg(0), dg(0), left(NULL), right(NULL) {
	if(cb == ce) { len = l[cb]; return; }
	int mid = (cb+ce) / 2;
	left = new Crane(cb, mid); right = new Crane(mid+1, ce);
	len = left->len + right->len;
}
void Crane::rotate(int a, int pt) {
	if(pt <= b) { dg += a; pdg += a; }
	else {
		int mid = (b+e) / 2;
		left->dg += pdg; left->pdg += pdg;
		right->dg += pdg; right->pdg += pdg;
		pdg = 0;
		if(pt <= mid) left->rotate(a, pt);
		right->rotate(a, pt);
		update();
	}
}

int main()
{
	int n, c, case_no, i, t;

	for(case_no = 0; scanf("%d %d", &n, &c) != EOF; case_no++) {
		if(case_no != 0) putchar('\n');
		for(i = 0; i < n; i++) scanf("%d", &l[i]);
		Crane crane(0, n-1); crane.rotate(90, 0);
		memset(alpha, 0, sizeof(alpha));
		for(t = 0; t < c; t++) {
			int p, d; scanf("%d %d", &p, &d);
			crane.rotate(d+180-alpha[p], p); alpha[p] = d+180;
			printf("%.2lf %.2lf\n", crane.xc(), crane.yc());
		}
	}
	
	return 0;
}