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문제

A non-empty array A consisting of N integers is given. A pair of integers (P, Q), such that 0 ≤ P ≤ Q < N, is called a slice of array A. The sum of a slice (P, Q) is the total of A[P] + A[P+1] + ... + A[Q].

Write a function:

class Solution { public int solution(int[] A); }

that, given an array A consisting of N integers, returns the maximum sum of any slice of A.

For example, given array A such that:

A[0] = 3 A[1] = 2 A[2] = -6
A[3] = 4 A[4] = 0
the function should return 5 because:

(3, 4) is a slice of A that has sum 4,
(2, 2) is a slice of A that has sum −6,
(0, 1) is a slice of A that has sum 5,
no other slice of A has sum greater than (0, 1).
Write an efficient algorithm for the following assumptions:

N is an integer within the range [1..1,000,000];
each element of array A is an integer within the range [−1,000,000..1,000,000];
the result will be an integer within the range [−2,147,483,648..2,147,483,647].
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코드

// you can also use imports, for example:
// import java.util.*;

// you can write to stdout for debugging purposes, e.g.
// System.out.println("this is a debug message");
import java.util.*;
class Solution {
    public int solution(int[] A) {
        int localMax = A[0];
        int globalMax = A[0];

        for(int i=1; i<A.length; i++){
            localMax = Math.max(A[i], localMax+A[i]);
            globalMax = Math.max(localMax, globalMax);
        }
        return globalMax;
        // Implement your solution here
    }
}
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풀이

MaxProfit 문제처럼, 해당 자리에서 가질 수 있는 최대값을 구해야한다.
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