import java.util.Scanner;
 
public class Main {
   public static int maxSubarraySum(int[] b) {
    int n = b.length - 1;
    if (n == 0) return 0;
 
    int[] p1 = new int[n + 1];
    int maxSum = 0;
 
    for (int i = 1; i <= n; ++i) {
        p1[i] = Math.max(Math.max(p1[i - 1] + b[i], b[i]), 0);
        maxSum = Math.max(maxSum, p1[i]);
    }
 
    return maxSum;
}
 
 
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
 
        int n = scanner.nextInt();
        int[] b = new int[n + 1]; // Adjust for 1-based indexing
 
        for (int i = 1; i <= n; ++i) {
            b[i] = scanner.nextInt();
        }
 
        int result = maxSubarraySum(b);
        System.out.println("Maximum subarray sum is " + result);
    }
}
 

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