题解 | 幻兽防御战

def main():
    import sys
    input = sys.stdin.readline

    n = int(input())
    dist = list(map(int, input().strip().split()))
    speed = list(map(int, input().strip().split()))
    t_ls = []
    for i in range(n):
        t_ls.append(1.0*dist[i]/speed[i])

    t_ls.sort()

    nums = 0
    shot = 0
    for t in t_ls:
        if t>shot:
            nums+=1
            shot+=1
        else:
            break
    print(nums)

if __name__ == "__main__":
    main()