Please tell me how to remove segmentation error in this code

#include
using namespace std;
int main()
{
int arr[1000];
int n;
cin>>n;
int maxsum=0;
int currentsum=0;
int cumsum[1000]={0};
int left=-1;
int right=-1;
cin>>arr[0];
cumsum[0]=arr[0];
for(int i=1;i<n;i++)
{
cin>>arr[i];
cumsum[i]=cumsum[i-1]+arr[i];
}
for(int i=1;i<n;i++){
for(int j=i;i<n;j++)
{
currentsum=0;
currentsum=cumsum[j]-cumsum[i-1];
if(currentsum>maxsum)
{
maxsum=currentsum;
left=i;
right=j;
}
}
}
cout<<currentsum;
for(int k=left;k<right;k++)
cout<<arr[k];
}