include[HTML_REMOVED]
include[HTML_REMOVED]
using namespace std;
const int N=1e5+10;
int n;
int h[N];
bool check(int mid){
int e=mid;
for(int i=1;i<=n;i++){
if(h[i]>e)e-=(h[i]-e);
else e+=(e-h[i]);
if(e<0)return false;
if(e>=1e5)return true;
}
return true;
}
int main(){
cin>>n;
for(int i=1;i<=n;i++)cin>>h[i];
int l=0,r=1e5;
while(l[HTML_REMOVED]>1;/最少单位的初始能量值尽可能靠左区间/
if(check(mid))r=mid;
else l=mid+1;
}
printf(“%d”,l);
return 0;
}