用c++设计一个折线类
时间: 2023-05-30 12:06:10 浏览: 79
折线类的设计如下:
```c
#include <stdio.h>
#include <stdlib.h>
// 定义点的结构体
typedef struct {
int x;
int y;
} Point;
// 定义折线类
typedef struct {
Point *points; // 存储折线上的点
int count; // 折线上的点数
} Polyline;
// 初始化折线
void initPolyline(Polyline *polyline) {
polyline->points = NULL;
polyline->count = 0;
}
// 添加点到折线
void addPoint(Polyline *polyline, Point point) {
polyline->count++;
polyline->points = (Point*)realloc(polyline->points, polyline->count * sizeof(Point));
polyline->points[polyline->count - 1] = point;
}
// 计算折线长度
double length(Polyline polyline) {
double len = 0;
for (int i = 0; i < polyline.count - 1; i++) {
int dx = polyline.points[i + 1].x - polyline.points[i].x;
int dy = polyline.points[i + 1].y - polyline.points[i].y;
len += sqrt(dx * dx + dy * dy);
}
return len;
}
int main() {
Polyline polyline;
initPolyline(&polyline);
Point p1 = {0, 0};
Point p2 = {1, 1};
Point p3 = {2, 3};
Point p4 = {3, 5};
addPoint(&polyline, p1);
addPoint(&polyline, p2);
addPoint(&polyline, p3);
addPoint(&polyline, p4);
printf("The length of the polyline is %.2f\n", length(polyline));
free(polyline.points);
return 0;
}
```
以上代码实现了一个简单的折线类,包括了初始化、添加点和计算折线长度的操作。在添加点时,使用了动态内存分配,以便可以添加任意数量的点。在计算折线长度时,使用了勾股定理计算每个线段的长度,并将它们相加得到总长度。