对区间的模糊排序

算法导论第三版第二部分7-6题

Interval find_intersection(vector<Interval> &array,int start,int end)
{int random = random_include_left_right(start,end);Interval key = array[end];array[end] = array[random];array[random] = key;key = array[end];for (int i = start; i < end; ++i) {if(array[i].left <= key.right && array[i].right>= key.left){if(array[i].left > key.left)key.left = array[i].left;if(array[i].right < key.right)key.right = array[i].right;}}return key;
}
int partition_right(vector<Interval>& array,int left,int start,int end)
{int i = start - 1;for (int j = start; j < end; ++j) {if(array[j].left <= left){i++;Interval temp = array[i];array[i] = array[j];array[j] = temp;}}Interval temp = array[i+1];array[i+1] = array[end];array[end] = temp;return i+1;
}
int partition_left(vector<Interval>& array,int right,int start,int end){int i= start - 1;for (int j = start; j < end; ++j) {if(array[j].right < right){i++;Interval temp = array[i];array[i] = array[j];array[j] = temp;}}Interval temp = array[i+1];array[i+1] = array[end];array[end] = temp;return i+1;
}
void interval_fuzzy_sort(vector<Interval> &array,int start,int end){if(start < end){Interval key = find_intersection(array,start,end);int right = partition_right(array,key.left,start,end);int left = partition_left(array,key.right,start,right);interval_fuzzy_sort(array,start,left-1);interval_fuzzy_sort(array,right+1,end);}
}

辅助类
1⃣️ 随机数代码
2⃣️ Interval

class Interval {
public:float left;float right;
public:Interval();Interval(int left,int right);
};Interval::Interval(){}
Interval::Interval(int left,int right):left(left),right(right){}