有哪些做兼职的设计网站/seo是怎么优化上去

http://poj.org/problem?id=1265

定理证明见Matrix67——最酷的证明：Pick定理另类证法

注意dx和dy是机器人下一步移动的方向，所以位置要累加。

完整代码：

/*0ms,372KB*/#include<cstdio>
#include<cstdlib>
const int mx = 105;struct point
{double x, y;point(double x = 0.0, double y = 0.0): x(x), y(y) {}void read() const{scanf("%lf%lf", &x, &y);}
};point a[mx];
int n;///oa x ob
inline double cross_product(point& a, point& b)
{return a.x * b.y - a.y * b.x;
}///求多边形面积。以原点为向量起点。注意ans[]要是顺时针顺序
double area()
{double sum = 0.0;a[n] = a[0];for (int i = 0; i < n; ++i) sum += cross_product(a[i], a[i + 1]);return sum / 2.0;
}int gcd(int a, int b)
{return b ? gcd(b, a % b) : a;
}int borderpoint()
{int cnt = 0;a[n] = a[0];for (int i = 0; i < n; ++i)cnt += gcd(abs((int)(a[i].x - a[i + 1].x)), abs((int)(a[i].y - a[i + 1].y)));return cnt;
}int main()
{int t, i, B;double A;scanf("%d", &t);for (int k = 1; k <= t; ++k){scanf("%d", &n);for (i = 1; i < n; ++i){a[i].read();a[i].x += a[i - 1].x;a[i].y += a[i - 1].y;}scanf("%*d%*d");A = area();B = borderpoint();printf("Scenario #%d:\n%d %d %.1f\n\n", k, (int)A + 1 - B / 2, B, A);}return 0;
}