题目是求通关等级的最小等级 二分答案加贪心即可 排序贪心最小值 二分答案求得符合条件等级中的最小值

def main():
    import sys
    n = int(input())
    data = list(map(int, sys.stdin.readline().strip().split()))
    data.sort()
  #检查是否可以过关
    def k(x):
        total = 0
        for i in data:
            if x >= i:
                x += 10
                total += 1 
        if total == n:
            return True
        else:
            return False

    left = 1
    right = max(data)
    ans = 0
    while left <= right:
        mid = (left + right) // 2
        if k(mid):
          #可以过关缩短右边界 均值向左侧接近 使mid更小
            right = mid - 1
          #存储最优解 防止最后mid不是答案的情况
            ans = mid
          #无法过关left向右侧逼近 增大mid值
        else:
            left = mid + 1
          #向上取整
    print((ans + 9) // 10)
if __name__ == "__main__":
    main()

#无注释版本：

```python
def main():
    import sys
    n = int(input())
    data = list(map(int, sys.stdin.readline().strip().split()))
    data.sort()
    def k(x):
        total = 0
        for i in data:
            if x >= i:
                x += 10
                total += 1 
        if total == n:
            return True
        else:
            return False

    left = 1
    right = max(data)
    ans = 0
    while left <= right:
        mid = (left + right) // 2
        if k(mid):
            right = mid - 1
            ans = mid
        else:
            left = mid + 1
    print((ans + 9) // 10)
if __name__ == "__main__":
    main()