Position(int xx = 0, int yy = 0, int zz = 0) : x(xx), y(yy), z(zz) {}
时间: 2024-04-04 19:15:41 浏览: 10
这是一个名为 `Position` 的类中的构造函数。它有三个参数,分别是 `xx`、`yy` 和 `zz`,它们都是整数类型。这个构造函数的作用是将传入的参数赋值给类的成员变量 `x`、`y` 和 `z`,并将它们初始化为默认值 0。也就是说,如果在创建 `Position` 对象时没有传入任何参数,那么它的三个成员变量都会被初始化为 0。
相关问题
优化这个代码barcode=input("请输入8位条形码:")total=0X,y=13Dosition in code =len/barcode)while position in code l=0: total += int(barcodelposition_ in_code-1]*xX,V=y,xXposition in code-=1if total%10==0:print("条形码扫码正确!")else:print("条形码有错误!"
这段代码可以进行一些优化。比如,可以使用 for 循环代替 while 循环,使用 range() 函数进行遍历。另外,在变量名上,可以使用下划线(_)代替空格。
改进后的代码如下:
barcode = input("请输入8位条形码:")
total = 0
x, y = 13, 2
for position in range(len(barcode)):
if position == 0:
x, y = 13, 2
total += int(barcode[position]) * x
x, y = y, x
if total % 10 == 0:
print("条形码扫码正确!")
else:
print("条形码有错误!")
这样的代码更加清晰、易读,并且比原来的代码更加高效。
#include<iostream> #include<cmath> #include<algorithm> using namespace std; struct point { int x, y, index; double theta; } p[30000], temp; int f(point& a, point& b) { if (a.theta == b.theta) { if (a.x == b.x && a.y > 0) return a.y * a.y > b.y * b.y; else return a.x * a.x + a.y * a.y < b.x* b.x + b.y * b.y; }return a.theta < b.theta; }int main() { int n; cin >> n; //input for (int i = 0; i < n; i++) { int x, y; cin >> p[i].x >> p[i].y; p[i].index = i + 1; }//exchange min_x to first position int min = p[0].x, minPosition = 0; for (int i = 1; i < n; i++) { minPosition = min <= p[i].x ? minPosition : i; min = min <= p[i].x ? min : p[i].x; }temp = p[0]; p[0] = p[minPosition]; p[minPosition] = temp; //cal atan2 for (int i = 1; i < n; i++) { p[i].x -= p[0].x; p[i].y -= p[0].y; p[i].theta = atan2(p[i].y, p[i].x); }//sort exclude min_x sort(p + 1, p + n, f); //output cout << n << endl; for (int i = 0; i < n; i++) { if (p[i].index == 1) { for (int j = i; j < n; j++) cout << p[j].index << endl; for (int j = 0; j < i; j++) cout << p[j].index << endl; break; } } }转为Java
以下是将给定的 C++ 代码转换为 Java 代码的结果:
```java
import java.util.Arrays;
import java.util.Comparator;
import java.util.Scanner;
public class Main {
static class Point {
int x, y, index;
double theta;
public Point(int x, int y, int index, double theta) {
this.x = x;
this.y = y;
this.index = index;
this.theta = theta;
}
}
static Point[] p = new Point[30000];
static int f(Point a, Point b) {
if (a.theta == b.theta) {
if (a.x == b.x && a.y > 0)
return a.y * a.y > b.y * b.y ? 1 : -1;
else
return a.x * a.x + a.y * a.y < b.x * b.x + b.y * b.y ? 1 : -1;
}
return a.theta < b.theta ? 1 : -1;
}
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
int n = scan.nextInt();
// input
for (int i = 0; i < n; i++) {
int x = scan.nextInt();
int y = scan.nextInt();
p[i] = new Point(x, y, i + 1, 0);
}
// exchange min_x to first position
int min = p[0].x, minPosition = 0;
for (int i = 1; i < n; i++) {
minPosition = min <= p[i].x ? minPosition : i;
min = min <= p[i].x ? min : p[i].x;
}
Point temp = p[0];
p[0] = p[minPosition];
p[minPosition] = temp;
// cal atan2
for (int i = 1; i < n; i++) {
p[i].x -= p[0].x;
p[i].y -= p[0].y;
p[i].theta = Math.atan2(p[i].y, p[i].x);
}
// sort exclude min_x
Arrays.sort(p, 1, n, new Comparator<Point>() {
@Override
public int compare(Point a, Point b) {
return f(a, b);
}
});
// output
System.out.println(n);
for (int i = 0; i < n; i++) {
if (p[i].index == 1) {
for (int j = i; j < n; j++)
System.out.println(p[j].index);
for (int j = 0; j < i; j++)
System.out.println(p[j].index);
break;
}
}
scan.close();
}
}
```