Envío 6265

Código

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();

        long totalCount = 0;
        HashMap<Integer, Long> leftPositive = new HashMap<>();
        ArrayList<Integer> leftPositiveIndexes = new ArrayList<>();

        long oldTotalCount=0;
        for(int i=0; i<n; i++){
            int x = scanner.nextInt();
            totalCount+=x;

            if(totalCount > 0){
                if(oldTotalCount<totalCount){
                    oldTotalCount = totalCount;
                    leftPositiveIndexes.add(i);
                    leftPositive.put(i, totalCount);
                }
            }
        }

        boolean flag = true;
        for(int i=0; i<leftPositiveIndexes.size(); i++){
            long left = leftPositive.get(i);
            long right = totalCount - left;

            if(right < 0){
                System.out.println(leftPositiveIndexes.get(i)+1);
                flag = false;
                break;
            }
        }

        if(flag){
            System.out.println("Impossible");
        }
    }
}