#include<bits/stdc++.h> using namespace std; int n,email[1005],cnt=0,flag=0; int main(){ freopen("email.in","r",stdin); freopen("email.out","w",stdout); cin>>n; for(int i=1;i<=n;i++){ cin>>email[i]; if(email[i]==1) flag=1; } for(int i=1;i<=n;i++){ if(email[i]==1){ if(email[i+1]1) cnt++; else cnt+=2; } } if(flag0) cout<<0<<endl; else cout<<cnt-1<<endl; fclose(stdin); fclose(stdout); return 0; }