均分纸牌

http://ybt.ssoier.cn:8088/problem_show.php?pid=1320

#include<bits/stdc++.h>
using namespace std;
int a[661];
int main()
{
	int n,sum=0,eve,ans=0;
	cin>>n;
	for(int i=1;i<=n;i++) 
	{
		cin>>a[i];
		sum+=a[i];
	}
	eve=sum/n;
	for(int i=1;i<=n;i++) a[i]-=eve;
	int st=1,ed=n;
	while(a[st]==0&&st<=ed) st++;
	while(a[ed]==0&&st<=ed) ed--;
	for(int i=st;i<=ed;i++)
	{
		if(a[i]==0) continue;
		a[i+1]+=a[i];
		a[i]=0;
		ans++;
	}
	cout<<ans;
	return 0;
}```