#include
#include
using namespace std;
int main(){
int m;
cin >> m;
int arr[1000];
bool checker=false;
for(int i=0;i<m;i++) {
cin >> arr[i];
}
cin.get();
int target;
cin >> target;
int i=0,j=m-1;
while(i<j) {
int sum=arr[i]+arr[j];
if(sum==target) {
cout << "found" << endl;
checker=true;
cout << "i=" << i << " j=" << j;
i++;
j--;
}
else if(sum>target) {
j--;
}
else if(sum<target) {
i++;
}
}
if(checker==false) {
cout << "not found";
}
return 0;
}