有一个数组,元素为线段,将数组内处于相交状态的线段放入迭代器
时间: 2024-03-20 22:43:48 浏览: 55
NOIP 数据结构课件
好的,我可以为您编写一个函数来实现这个功能。假设每个线段由其起点和终点坐标表示,函数的输入参数为一个包含多个线段的数组,输出为一个迭代器,包含所有相交的线段。以下是一个可能的实现:
```cpp
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
struct LineSegment {
int x1, y1, x2, y2;
};
bool isIntersecting(LineSegment a, LineSegment b) {
int x1 = a.x1, y1 = a.y1, x2 = a.x2, y2 = a.y2;
int x3 = b.x1, y3 = b.y1, x4 = b.x2, y4 = b.y2;
int d = (y2 - y1) * (x4 - x3) - (x2 - x1) * (y4 - y3);
if (d == 0) {
return false;
}
double t = ((x3 - x1) * (y4 - y3) - (y3 - y1) * (x4 - x3)) / (double)d;
double u = ((x2 - x1) * (y3 - y1) - (y2 - y1) * (x3 - x1)) / (double)d;
if (t >= 0 && t <= 1 && u >= 0 && u <= 1) {
return true;
}
return false;
}
vector<LineSegment> findIntersectingSegments(vector<LineSegment>& segments) {
vector<LineSegment> result;
for (int i = 0; i < segments.size(); i++) {
for (int j = i + 1; j < segments.size(); j++) {
if (isIntersecting(segments[i], segments[j])) {
result.push_back(segments[i]);
result.push_back(segments[j]);
}
}
}
return result;
}
int main() {
vector<LineSegment> segments = {{0, 0, 1, 1}, {1, 0, 0, 1}, {0, 0, 0, 1}, {0, 1, 1, 1}};
vector<LineSegment> intersectingSegments = findIntersectingSegments(segments);
cout << "Intersecting segments:" << endl;
for (auto segment : intersectingSegments) {
cout << "(" << segment.x1 << "," << segment.y1 << ") - (" << segment.x2 << "," << segment.y2 << ")" << endl;
}
return 0;
}
```
该函数采用了暴力枚举的方法,遍历每一对线段,并检查它们是否相交。如果两个线段相交,则将它们都放入结果迭代器中。isIntersecting 函数用于检查两个线段是否相交。它首先计算两个线段的交点,然后检查这个交点是否在两个线段的范围内。注意,这个函数假设输入的线段不平行。如果需要处理平行线段的情况,需要进行额外的检查。
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