记录编号	128415	评测结果	AAAAAAAAAA
题目名称	[NOIP 2010冲刺十二]奶牛晒衣服	最终得分	100
用户昵称	mzy	是否通过	通过
代码语言	C++	运行时间	0.241 s
提交时间	2014-10-17 17:10:02	内存使用	2.22 MiB

# include <iostream>
# include <cstdio>
using namespace std;

int n,A,B;
int a[500005];
int l=0,r=0,mid,ans;

bool check(int k)
{
	int cnt = 0;
	int t = k*A;
	for (int i=1;i<=n;++i)
	{
		if (a[i]<=t)  continue;
		if (!((a[i]-t)%B))
			cnt += (a[i]-t)/B;
		else
			cnt += (a[i]-t)/B+1;
	}
	if (cnt <= k)  return 1;
	else  return 0;	
}

int main()
{
	freopen("dry.in", "r", stdin);
	freopen("dry.out", "w", stdout);
	
	scanf("%d%d%d", &n, &A, &B);
	for (int i=1;i<=n;++i)
	{
		scanf("%d", &a[i]);
		r = max(r,a[i]);
	}

	while (l<=r)
	{
		mid = (l+r)>>1;
		if (check(mid))
		{
			ans = mid;
			r = mid-1;
		}
		else
			l = mid+1;
	}
	
	printf("%d\n", ans);
	
	return 0;
}