查找开始和结束日期数组中的重叠

def find_overlapping_dates(date_array):
    # 按照开始日期进行排序
    sorted_dates = sorted(date_array, key=lambda x: x[0])
    
    overlapping_dates = []
    current_start, current_end = sorted_dates[0]
    
    for i in range(1, len(sorted_dates)):
        next_start, next_end = sorted_dates[i]
        
        if current_end >= next_start:
            # 存在重叠部分
            overlapping_dates.append((max(current_start, next_start), min(current_end, next_end)))
            current_end = max(current_end, next_end)
        else:
            # 不存在重叠部分，更新当前日期区间
            current_start, current_end = next_start, next_end
    
    return overlapping_dates