1732. 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

Explanation

for문 돌면서 i 인덱스까지의 값을 sum에 더해두고, 저장해둔 max값보다 sum이 더 크면 max값을 sum으로 갱신하며 해결

 

Time Complexity

O(N)

class Solution {
    public int largestAltitude(int[] gain) {
        int max = 0;
        int sum = 0;
        for(int i = 0; i < gain.length; i++){
            sum+=gain[i];
            if(sum>max){
                max=sum;
            }
        }
        return max;
    }
}