P1031均分纸牌

#include<bits/stdc++.h>
using namespace std;
int n,a[105],ave,step;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>a[i];
		ave+=a[i];
	}
	ave/=n;
	for(int i=1;i<=n;i++){
		a[i]-=ave;
	}
	int i=1,j=n;
	while(i<j&&a[i]==0) i++;
	while(i<j&&a[j]==0) j--;
	while(i<j){
		a[i+1]+=a[i];
		step++;
		i++;
		while(i<j&&a[i+1]==0) i++;
	}
	cout<<step;
	return 0;
}