题意:给出一条直线,在直线上取一点,其垂直x,y轴作成一个,求矩阵中所有包含的点的x,y坐标之和的最大值。
思路:对于一个任意一点我们计算公式,对于任意一点$(x, y)$,有$(x+y)^2 + (x+y)(xy+1)$,枚举一个未知量,得另一个未知量向下取整即可。
/** @Date : 2017-07-04 14:52:58 * @FileName: B 数学.cpp * @Platform: Windows * @Author : Lweleth (SoungEarlf@gmail.com) * @Link : https://github.com/ * @Version : $Id$ */#include#define LL long long#define PII pair#define MP(x, y) make_pair((x),(y))#define fi first#define se second#define PB(x) push_back((x))#define MMG(x) memset((x), -1,sizeof(x))#define MMF(x) memset((x),0,sizeof(x))#define MMI(x) memset((x), INF, sizeof(x))using namespace std;const int INF = 0x3f3f3f3f;const int N = 1e5+20;const double eps = 1e-8;int main(){ double m, b; while(cin >> m >> b) { double len = m * b; LL ma = 0; for(double x = 0; x <= len; x+=1) { double y = floor(b - x / m); LL t = (LL)(x + y) * (x + y) + (LL)(x + y)*(x * y + 1); ma = max(ma, t); //cout << x << y <<" " <