LeetCode - Easy - 1732. Find the Highest Altitude-蒲公英云

LeetCode - Easy - 1732. Find the Highest Altitude

Topic

Array

Description

https://leetcode.com/problems/find-the-highest-altitude/

There is a biker going on a road trip. The road trip consists of n + 1 points at different altitudes. The biker starts his trip on point 0 with altitude equal 0.

You are given an integer array gain of length n where gain[i] is the net gain in altitude between points i and i + 1 for all (0 <= i < n). Return the highest altitude of a point.

Example 1:

Input: gain = [-5,1,5,0,-7]
Output: 1
Explanation: The altitudes are [0,-5,-4,1,1,-6]. The highest is 1.

Example 2:

Input: gain = [-4,-3,-2,-1,4,3,2]
Output: 0
Explanation: The altitudes are [0,-4,-7,-9,-10,-6,-3,-1]. The highest is 0.

Constraints:

n == gain.length
1 <= n <= 100
-100 <= gain[i] <= 100

Analysis

略

Submission

public class FindTheHighestAltitude { 
    public int largestAltitude(int[] gain) { 
        int max = 0, sum = 0;
        for (int num : gain) { 
            sum += num;
            if (sum > max)
                max = sum;
        }
        return max;
    }
}

Test

import static org.junit.Assert.*;
import org.junit.Test;
public class FindTheHighestAltitudeTest { 
    @Test
    public void test() { 
        FindTheHighestAltitude obj = new FindTheHighestAltitude();
        assertEquals(1, obj.largestAltitude(new int[] { -5, 1, 5, 0, -7}));
        assertEquals(0, obj.largestAltitude(new int[] { -4, -3, -2, -1, 4, 3, 2}));
    }
}