#include<bits/stdc++.h>
using namespace std;
#define int long long
int dp[600005][2];
int sz[600005];
signed main(){
int n;
cin>>n;
for(int i=1;i<=n;i++){
	cin>>sz[i];
	sz[i+n]=sz[i];
}
memset(dp,0x7f,sizeof(dp));
int ans=1000000000000;
dp[1][1]=sz[1];

for(int i=2;i<=n;i++){
	dp[i][0]=dp[i-1][1];
	dp[i][1]=min(dp[i-1][1],dp[i-1][0])+sz[i];
}
ans=min(dp[n][1],dp[n][0]);
memset(dp,0x7f,sizeof(dp));
dp[n][1]=sz[n];
for(int i=n+1;i<=2*n-1;i++){
	dp[i][0]=dp[i-1][1];
	dp[i][1]=min(dp[i-1][1],dp[i-1][0])+sz[i];
}
ans=min(ans,min(dp[2*n-1][1],dp[2*n-1][0]));
cout<<ans;
}